msm: Add back voice svc driver

Add voice svc driver back in kernel 4.9 to help userspace
ims module build which has dependency on it for Kai device Android M
bring up with kernel 4.9

voice svc driver build is put under conditional check, so that
it is included only for required target of Kai

Change-Id: I6d801ddb0bc20d05fb4aadf488e560b39ab931bd
Signed-off-by: Shalini Manjunatha <shalma@codeaurora.org>