HSD #14015618796: crypto: intel_fcs: support concurrent fcs clients requests

commit 966aff272853da511bab92e4533515cbffa6f79c from
https://github.com/altera-opensource/linux-socfpga.git

 socfpga-5.15.30-lts.

The current driver does not support concurrent clients sending IOCTL
commands. The driver must implement a mutex lock at the start of an IOCTL
command before allocating any memory from the stack and before initiating
any SVC commands to the mailbox.

Signed-off-by: Ang Tien Sung <tien.sung.ang@intel.com>
Signed-off-by: Liwei Song <liwei.song@windriver.com>