drivers: msm: Fix a handful of compiler warnings

Compiling the kernel with the -O2 GCC flag reveals a number
of warnings relating to potentially uninitialized variables
and other edge cases.

Change-Id: I3758dbe1af276d79f55188b9f2db850c730acb80
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
[gbroner@codeaurora.org: drop changes to all file besides
ufs-msm.c and ufshcd.c]
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>