mmc: msm_sdcc: fix gray code values

DLL (Delay Locked Loop) HW block inside SDCC4 controller
can take 16 different phases (0 to 15). Value of these phases
should be written in gray code format in HW register.

But gray code values used in driver are wrong and differs
from standard definition of gray codes. This patch fixes the
gray code values to be compliant with standard definition of
gray codes.

CRs-fixed: 334493
Change-Id: I347fee0c801ae7cdb177ea4066f18af6f49a3fdc
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>