intel: fcs: Validate the data address pointer and size before using it

commit 55cd99af3d5aa500ec3dbffe53c1583a70a55e0e from
https://github.com/altera-opensource/linux-socfpga.git

 socfpga-5.15.30-lts.

Make sure the code validate the data address pointer and size before
using it. The purpose of this patch is to fix the error detected by
Klocwork.

Signed-off-by: Siew Chin Lim <elly.siew.chin.lim@intel.com>
Signed-off-by: Liwei Song <liwei.song@windriver.com>