PhoshPanel: define PHOSH_TYPE_PANEL properly

The convention is to have the _TYPE_ after the prefix

src/panel.c

@@ -194,7 +194,7 @@ GtkWidget *
 phosh_panel_new (struct zwlr_layer_shell_v1 *layer_shell,
                  struct wl_output *wl_output)
 {
-  return g_object_new (PHOSH_PANEL_TYPE,
+  return g_object_new (PHOSH_TYPE_PANEL,
                        "layer-shell", layer_shell,
                        "wl-output", wl_output,
                        "height", PHOSH_PANEL_HEIGHT,

src/panel.h

@@ -8,7 +8,7 @@
 
 #include "layersurface.h"
 
-#define PHOSH_PANEL_TYPE                 (phosh_panel_get_type ())
+#define PHOSH_TYPE_PANEL                 (phosh_panel_get_type ())
 
 G_DECLARE_FINAL_TYPE (PhoshPanel, phosh_panel, PHOSH, PANEL, PhoshLayerSurface)