cogl: Remove CoglBool, use gboolean instead

This basically reverts commit 54735dec, which tried to avoid the
GLib-defined types in favor the standard C ones. One exception to this
is the bool type, for which the commit introduces a new type CoglBool.

Let's just get rid of this type in favor of having consistency with the
GLib types. Note by the way that neither CoglBool nor gboolean (which
has a size of `int`) are completely compatible with bool (size `char`).

https://gitlab.gnome.org/GNOME/mutter/merge_requests/321

cogl/cogl-pango/cogl-pango-fontmap.c

@@ -153,7 +153,7 @@ cogl_pango_font_map_clear_glyph_cache (CoglPangoFontMap *fm)
 
 void
 cogl_pango_font_map_set_use_mipmapping (CoglPangoFontMap *fm,
-                                        CoglBool          value)
+                                        gboolean          value)
 {
   PangoRenderer *renderer = _cogl_pango_font_map_get_renderer (fm);
 
@@ -161,7 +161,7 @@ cogl_pango_font_map_set_use_mipmapping (CoglPangoFontMap *fm,
                                            value);
 }
 
-CoglBool
+gboolean
 cogl_pango_font_map_get_use_mipmapping (CoglPangoFontMap *fm)
 {
   PangoRenderer *renderer = _cogl_pango_font_map_get_renderer (fm);