meson: Forbid implicit fallthrough

meson.build

@@ -47,6 +47,7 @@ test_c_args = [
   '-Werror=return-type',
   '-Werror=shift-count-overflow',
   '-Werror=shift-overflow=2',
+  '-Werror=implicit-fallthrough=3',
   '-Wfloat-equal',
   '-Wformat-nonliteral',
   '-Wformat-security',

src/wwan/phosh-wwan-mm.c

@@ -245,12 +245,16 @@ phosh_wwan_mm_get_property (GObject *object,
   switch (property_id) {
   case PHOSH_WWAN_MM_PROP_SIGNAL_QUALITY:
     g_value_set_uint (value, priv->signal_quality);
+    break;
   case PHOSH_WWAN_MM_PROP_ACCESS_TEC:
     g_value_set_string (value, priv->access_tec);
+    break;
   case PHOSH_WWAN_MM_PROP_UNLOCKED:
     g_value_set_boolean (value, priv->unlocked);
+    break;
   case PHOSH_WWAN_MM_PROP_SIM:
     g_value_set_boolean (value, priv->sim);
+    break;
   default:
     G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     break;