ofono: add missing header inclusions

This is a "leaf" header and doesn't even have header guards, but
it still seems natural that the header should pull in its own declarations
rather than relying on the including source file to ensure that they
are included.

src/common.h

@@ -19,6 +19,10 @@
  *
  */
 
+#include <glib.h>
+
+#include <ofono/types.h>
+
 /* 27.007 Section 7.3 <AcT> */
 enum access_technology {
 	ACCESS_TECHNOLOGY_GSM =			0,