Revert "target-arm: Avoid g_hash_table_get_keys()"

Since we now require GLib 2.22+ (commit f40685c6), we don't have to
work around lack of g_hash_table_get_keys() anymore.

This reverts commit 82a3a118.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1432749090-4698-1-git-send-email-armbru@redhat.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

target-arm/helper.c

@@ -294,23 +294,15 @@ static gint cpreg_key_compare(gconstpointer a, gconstpointer b)
     return 0;
 }
 
-static void cpreg_make_keylist(gpointer key, gpointer value, gpointer udata)
-{
-    GList **plist = udata;
-
-    *plist = g_list_prepend(*plist, key);
-}
-
 void init_cpreg_list(ARMCPU *cpu)
 {
     /* Initialise the cpreg_tuples[] array based on the cp_regs hash.
      * Note that we require cpreg_tuples[] to be sorted by key ID.
      */
-    GList *keys = NULL;
+    GList *keys;
     int arraylen;
 
-    g_hash_table_foreach(cpu->cp_regs, cpreg_make_keylist, &keys);
-
+    keys = g_hash_table_get_keys(cpu->cp_regs);
     keys = g_list_sort(keys, cpreg_key_compare);
 
     cpu->cpreg_array_len = 0;