su: Remove dead code

This is useless, _and_ comparing with an uninitialized variable. Not
smart.

Thanks to Jann Horn <jann@thejh.net> for the heads up.

Change-Id: I637b4ecb40f735b668408373003d862685baa914

Author: rmcc

su.c

@@ -434,7 +434,6 @@ int su_main(int argc, char *argv[], int need_client) {
             .name = "",
         },
     };
-    struct stat st;
     int c, socket_serv_fd, fd;
     char buf[64], *result;
     policy_t dballow;
@@ -536,12 +535,6 @@ int su_main(int argc, char *argv[], int need_client) {
         allow(&ctx, NULL);
     }
 
-    // always allow if this is the superuser uid
-    // superuser needs to be able to reenable itself when disabled...
-    if (ctx.from.uid == st.st_uid) {
-        allow(&ctx, NULL);
-    }
-
     // check if superuser is disabled completely
     if (access_disabled(&ctx.from)) {
         ALOGD("access_disabled");