Logging H_CALL return codes in PLPKS driver are easy to confuse with
Linux error codes.

Let the caller of the function log the converted linux error code.
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221106205839.600442-5-nayna@linux.ibm.com