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>

drivers/scsi/esas2r/esas2r_ioctl.c

@@ -1962,7 +1962,7 @@ int esas2r_read_fs(struct esas2r_adapter *a, char *buf, long off, int count)
 			(struct esas2r_ioctl_fs *)a->fs_api_buffer;
 
 		/* If another flash request is already in progress, return. */
-		if (down_interruptible(&a->fs_api_semaphore)) {
+		if (mutex_lock_interruptible(&a->fs_api_mutex)) {
 busy:
 			fs->status = ATTO_STS_OUT_OF_RSRC;
 			return -EBUSY;
@@ -1978,7 +1978,7 @@ busy:
 		rq = esas2r_alloc_request(a);
 		if (rq == NULL) {
 			esas2r_debug("esas2r_read_fs: out of requests");
-			up(&a->fs_api_semaphore);
+			mutex_unlock(&a->fs_api_mutex);
 			goto busy;
 		}
 
@@ -2006,7 +2006,7 @@ busy:
 		;
 dont_wait:
 		/* Free the request and keep going */
-		up(&a->fs_api_semaphore);
+		mutex_unlock(&a->fs_api_mutex);
 		esas2r_free_request(a, (struct esas2r_request *)rq);
 
 		/* Pick up possible error code from above */