Fix for SSH connection loss after FFDC in boot_devices suite.

This changes includes:
  - Open SSH connection before each test case run.
  - Close SSH connection post each test case run.
  - Added pre and post test cases execution keywords.
  - Removed suite setup and teardown.

Resolves openbmc/openbmc-test-automation#450

Change-Id: Ibb44b0247cb31f63e670593cdb963b963f36d86f
Signed-off-by: Sweta Potthuri <spotthur@in.ibm.com>
1 file changed