utils: avoid redundant set/endpwent around getpwuid

set/endpwent are only required for iterating through passwd entries
using getpwent(). Since we are explicitly requesting a passwd entry
for a uid then the set/endpwent calls are redundant.

Removing these redundant calls is required for building on Android
since their C library doesn't implement these.

https://bugzilla.gnome.org/show_bug.cgi?id=645881

glib/gutils.c

@@ -743,13 +743,7 @@ g_get_user_database_entry (void)
 
         if (!pw)
           {
-#ifndef __BIONIC__
-            setpwent ();
-#endif
             pw = getpwuid (getuid ());
-#ifndef __BIONIC__
-            endpwent ();
-#endif
           }
         if (pw)
           {