msm: synx: change kzalloc to vzalloc

Change the memory allocation function to vzalloc
as there is no need for physically contiguous memory
for the client structure.

Change-Id: Ic6377953c6acc6442eea8fbee2e1798ac32ebebb
Signed-off-by: Sumukh Hallymysore Ravindra <shallymy@codeaurora.org>