scsi: ufs: clear unit attention after every new device probe

We are currently clearing the UNIT ATTENTION condition on UFS DEVICE
well-known logical unit only after the first device probe. This has
worked for embedded UFS devices but won't work for removable UFS devices.
This change takes the safer option of clearing the UNIT ATTENTION condition
after every new device probe which should work with both removable and
embedded UFS devices.

Change-Id: Ic2632aa1667a0e58a1ce248bfd6c99d1be2c4788
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>