Update attach logic in VolumeEncryptionTest

Pick the same logic as volume attach tests have, when after
volume attach server is rebooted to make sure guest OS
recognize new device.

Change-Id: I92098c7d994dc7d85643da29380866a805f4e869
Related-Prod: PRODX-5292
(cherry picked from commit 40bbd545a59328363c9ca8785d0d1eaed1eb8aed)
(cherry picked from commit c17ff148134712b8c8606608ef7d7abc789605ce)
(cherry picked from commit ff5888b9c37ff032f8314f1cbe2c121c48451eb5)
(cherry picked from commit f114587a68193407cbff7ebdc02bc6ce62204bf8)
(cherry picked from commit ac0a4a0d4d6c515f9739dd9f2ab35b235a3715d1)
1 file changed