bfa: fix bfa_fcb_itnim_alloc() error handling

The caller assumes that "itnim" is NULL on error and non-NULL on success
but really "itnim" is uninitialized on error.  This function should just
use normal error handling where it returns zero on success and negative
on failure.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Anil Gurumurthy <anil.gurumurthy@qlogic.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>