i2c-msm-v2: initialize xfer mode structures in qup init

Unitialized blk mode structure cause crash when DMA gets disabled
from dt, forcing use of block mode for transfers > 64 bytes.
This patch initialize the xfer mode structures during the qup
intialization for all the xfer modes to avoid any unitialized access.

Change-Id: Ia2e44298948c8bbe15d751f9499cfd1c9b0ece4c
Signed-off-by: Ankit Gupta <ankgupta@codeaurora.org>