soc: qcom: smd: Validate read and write addresses

The address from which data has to be read and the address to which the
SMD data has to be written are calculated based on the head and tail
pointers for that SMD FIFO. As these pointer values depend on SMEM
content, there is a possibility that these values could be invalid due
to corruption of SMEM.

Validate the read and write addresses to be with in the limits of
receive and send FIFO limits respectively.

CRs-Fixed: 550527
Change-Id: Idb8ef3b3ad434fdd099271f760988fde4bd0b143
Signed-off-by: Zaheerulla Meer <zmeer@codeaurora.org>