scsi: esas2r: Replace semaphore fs_api_semaphore with mutex

The semaphore 'fs_api_semaphore' is used as a simple mutex, so it should
be written as one. Semaphores are going away in the future.

Signed-off-by: Binoy Jayan <binoy.jayan@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/esas2r/esas2r.h b/drivers/scsi/esas2r/esas2r.h
index c5013de..1da6407 100644
--- a/drivers/scsi/esas2r/esas2r.h
+++ b/drivers/scsi/esas2r/esas2r.h
@@ -946,7 +946,7 @@
 	struct esas2r_mem_desc *vrq_mds;
 	int num_vrqs;
 	struct mutex fm_api_mutex;
-	struct semaphore fs_api_semaphore;
+	struct mutex fs_api_mutex;
 	struct semaphore nvram_semaphore;
 	struct atto_ioctl *local_atto_ioctl;
 	u8 fw_coredump_buff[ESAS2R_FWCOREDUMP_SZ];