staging: lustre: lnet: return of an error code should be negative

Return value of error codes should typically be negative.
Issue reported by checkpatch.pl
Signed-off-by: Sumit Pundir <pundirsumit11@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/selftest/framework.c

@@ -187,7 +187,7 @@ sfw_del_session_timer(void)
 		return 0;
 	}
 
-	return EBUSY; /* racing with sfw_session_expired() */
+	return -EBUSY; /* racing with sfw_session_expired() */
 }
 
 static void