mu: fix some compiler warnings

lib/Makefile.am

@@ -24,6 +24,7 @@ AM_CFLAGS=					\
 	$(WARN_CFLAGS)				\
 	-Wno-format-nonliteral			\
 	-Wno-switch-enum			\
+	-Wno-suggest-attribute=format		\
 	$(GMIME_CFLAGS)				\
 	$(GLIB_CFLAGS)				\
 	$(GUILE_CFLAGS)

lib/mu-script.c

@@ -308,8 +308,8 @@ gboolean
 mu_script_guile_run (MuScriptInfo *msi, const char *muhome,
 		     const char **args, GError **err)
 {
-	char *mainargs, *expr;
-	char *argv[] = {
+	char	*mainargs, *expr;
+	const char * argv[] = {
 		"guile", "-l", NULL, "-c", NULL, NULL
 	};
 

lib/mu-store-write.cc

@@ -684,7 +684,7 @@ each_contact_check_if_personal (MuMsgContact *contact, MsgDoc *msgdoc)
 	return TRUE;
 }
 
-Xapian::Document
+static Xapian::Document
 new_doc_from_message (MuStore *store, MuMsg *msg)
 {
 	Xapian::Document doc;
@@ -738,7 +738,7 @@ update_threading_info (Xapian::WritableDatabase* db,
 }
 
 
-unsigned
+static unsigned
 add_or_update_msg (MuStore *store, unsigned docid, MuMsg *msg, GError **err)
 {
 	g_return_val_if_fail (store, MU_STORE_INVALID_DOCID);