Fix return value of selinux_android_restorecon.

Change I4a380caab7f8481c33eb64fcdb16b6cabe918ebd unified
the init and libselinux restorecon code but introduced a bug
by changing the return value of selinux_android_restorecon
on errors from -1 (as in libselinux) to -errno (as in the init
built-in command).  Change it back as there are various callers
assuming the libselinux behavior and init does not actually rely
on the -errno behavior in the utils code and handles it correctly
in the built-in command functions themselves.

Change-Id: I6ed5b644820eb07c061d8a2a116511aeb7401df4
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
diff --git a/src/android.c b/src/android.c
index 554828e..5810e63 100644
--- a/src/android.c
+++ b/src/android.c
@@ -713,11 +713,11 @@
     int i;
 
     if (selabel_lookup(sehandle, &secontext, pathname, sb->st_mode) < 0)
-        return -errno;
+        return -1;
 
     if (lgetfilecon(pathname, &oldsecontext) < 0) {
         freecon(secontext);
-        return -errno;
+        return -1;
     }
 
     if (strcmp(oldsecontext, secontext) != 0) {
@@ -727,7 +727,7 @@
                         pathname, secontext, strerror(errno));
             freecon(oldsecontext);
             freecon(secontext);
-            return -errno;
+            return -1;
         }
     }
     freecon(oldsecontext);
@@ -754,7 +754,7 @@
         return 0;
 
     if (lstat(pathname, &sb) < 0)
-        return -errno;
+        return -1;
 
     return restorecon_sb(pathname, &sb, false);
 }