Remove get_ram_size_in_mb, get_number_of_vcpus, etc

get_ram_size_in_mb() is never used since the commit
Ia34d7c75ad05f7658d1abb7bebeb1bbd271fd089 when adding this method
at first time.

get_number_of_vcpus() is used in test_verify_created_server_vcpus
only in whole OpenStack projects. And the method just calls exec_command()
with a simple command. It is not necessary to define it as common method.

get_hostname() is used only in test_host_name_is_same_as_server_name
only in whole OpenStack projects. And the method just calls exec_command()
with a simple command. It is not necessary to define it as common method.

Before defining remote_client as stable interface, this patch removes the
methods for the cleanup.

NOTE: This removal affects to Tempest only without
      any other projects.

Change-Id: I638055d728d7406cd5ad64ee13701ef826287dd0
diff --git a/tempest/api/compute/servers/test_create_server.py b/tempest/api/compute/servers/test_create_server.py
index fd5e50e..38dbb50 100644
--- a/tempest/api/compute/servers/test_create_server.py
+++ b/tempest/api/compute/servers/test_create_server.py
@@ -122,7 +122,8 @@
             self.validation_resources['keypair']['private_key'],
             server=self.server,
             servers_client=self.client)
-        self.assertEqual(flavor['vcpus'], linux_client.get_number_of_vcpus())
+        output = linux_client.exec_command('grep -c ^processor /proc/cpuinfo')
+        self.assertEqual(flavor['vcpus'], int(output))
 
     @decorators.idempotent_id('ac1ad47f-984b-4441-9274-c9079b7a0666')
     @testtools.skipUnless(CONF.validation.run_validation,
@@ -136,7 +137,7 @@
             self.validation_resources['keypair']['private_key'],
             server=self.server,
             servers_client=self.client)
-        hostname = linux_client.get_hostname()
+        hostname = linux_client.exec_command("hostname").rstrip()
         msg = ('Failed while verifying servername equals hostname. Expected '
                'hostname "%s" but got "%s".' % (self.name, hostname))
         self.assertEqual(self.name.lower(), hostname, msg)
diff --git a/tempest/common/utils/linux/remote_client.py b/tempest/common/utils/linux/remote_client.py
index 1487c1d..9bb2fce 100644
--- a/tempest/common/utils/linux/remote_client.py
+++ b/tempest/common/utils/linux/remote_client.py
@@ -99,20 +99,6 @@
         """
         self.ssh_client.test_connection_auth()
 
-    def get_hostname(self):
-        # Get host name using command "hostname"
-        actual_hostname = self.exec_command("hostname").rstrip()
-        return actual_hostname
-
-    def get_ram_size_in_mb(self):
-        output = self.exec_command('free -m | grep Mem')
-        if output:
-            return output.split()[1]
-
-    def get_number_of_vcpus(self):
-        output = self.exec_command('grep -c ^processor /proc/cpuinfo')
-        return int(output)
-
     def get_disks(self):
         # Select root disk devices as shown by lsblk
         command = 'lsblk -lb --nodeps'
diff --git a/tempest/tests/common/utils/linux/test_remote_client.py b/tempest/tests/common/utils/linux/test_remote_client.py
index 5be6229..1c5e89f 100644
--- a/tempest/tests/common/utils/linux/test_remote_client.py
+++ b/tempest/tests/common/utils/linux/test_remote_client.py
@@ -67,16 +67,6 @@
         self.ssh_mock = self.useFixture(mockpatch.PatchObject(self.conn,
                                                               'ssh_client'))
 
-    def test_get_hostname(self):
-        self.ssh_mock.mock.exec_command.return_value = 'fake_hostname'
-        self.assertEqual(self.conn.get_hostname(), 'fake_hostname')
-
-    def test_get_ram_size(self):
-        free_output = "Mem:         48294      45738       2555          0" \
-                      "402      40346"
-        self.ssh_mock.mock.exec_command.return_value = free_output
-        self.assertEqual(self.conn.get_ram_size_in_mb(), '48294')
-
     def test_write_to_console_regular_str(self):
         self.conn.write_to_console('test')
         self._assert_exec_called_with(
@@ -102,11 +92,6 @@
         cmd = "set -eu -o pipefail; PATH=$PATH:/sbin; " + cmd
         self.ssh_mock.mock.exec_command.assert_called_with(cmd)
 
-    def test_get_number_of_vcpus(self):
-        self.ssh_mock.mock.exec_command.return_value = '16'
-        self.assertEqual(self.conn.get_number_of_vcpus(), 16)
-        self._assert_exec_called_with('grep -c ^processor /proc/cpuinfo')
-
     def test_get_disks(self):
         output_lsblk = """\
 NAME       MAJ:MIN    RM          SIZE RO TYPE MOUNTPOINT