Use glib memory allocation and free functions

qemu_malloc/qemu_free no longer exist after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/check-qstring.c b/check-qstring.c
index c9bafc2..93bd475 100644
--- a/check-qstring.c
+++ b/check-qstring.c
@@ -32,8 +32,8 @@
     fail_unless(qobject_type(QOBJECT(qstring)) == QTYPE_QSTRING);
 
     // destroy doesn't exit yet
-    qemu_free(qstring->string);
-    qemu_free(qstring);
+    g_free(qstring->string);
+    g_free(qstring);
 }
 END_TEST