Fix Nova API misimplementation for security groups

The Compute API reference [1] states that the 'description' parameter
is optional when creating a security group. Consequently, omitting this
parameter (or passing an empty string or a whitespace) is allowed.

This patch removes those verifications that should not exist so that
change I404dd30c7dac4b8a9e01cf2ea62fa404fdcce3de can pass Tempest
checks.

[1]: http://developer.openstack.org/api-ref-compute-v2-ext.html#createSecGroup

Change-Id: I504f00cecbd004f00b3553e8a23c2b3870405050
Related-Bug: #1434172
1 file changed