scsi: ufs: fix deadlock during runtime resume

Commit e21cdd59b6fbaeaf3ab0043fc49287f554fa8696 (scsi: ufs: Change power
mode at run-time via debug-fs) has introduced bug where
pm_runtime_get_sync() might get called in UFS driver's runtime resume
callback context which will cause the deadlock as pm_runtime_get_sync()
waits for the runtime resume callback to finish.

This change fixes the above bug by moving pm_runtime_get_sync() call out
of runtime resume callback context.

Change-Id: I1efa68510eb2545fc043dfa4d8bfe6f6c36ef6a8
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>