Remove unused local variable.

Clang compiler gives it a warning and error.

Change-Id: Id35b740e265b393b5e31e05bd83544f391d8ff08
diff --git a/adb/remount_service.c b/adb/remount_service.c
index 05d3169..9746f9a 100644
--- a/adb/remount_service.c
+++ b/adb/remount_service.c
@@ -115,7 +115,6 @@
 static int remount(const char* dir, int* dir_ro)
 {
     char *dev;
-    int OFF = 0;
 
     if (dir_ro == 0) {
         return 0;