[ui] Add font to renderer when loading

This causes some problems with linking if libQFgui is linked with
libQFrenderer (which is necessary in the long run), but it seems
everything gets away with it for now (which, tbh, I don't like).

include/QF/ui/font.h

@@ -51,6 +51,7 @@ typedef struct font_s {
 	FT_Long     num_glyphs;
 	vrect_t    *glyph_rects;
 	vec2i_t    *glyph_bearings;
+	uint32_t    fontid;
 } font_t;
 
 void Font_Init (void);

libs/ruamoko/rua_gui.c

@@ -60,7 +60,7 @@ bi (Font_Load)
 
 	QFile      *font_file = QFS_FOpenFile (font_path);
 	font_t     *font = Font_Load (font_file, font_size);
-	R_INT (pr) = r_funcs->Draw_AddFont (font);
+	R_INT (pr) = font->fontid;
 }
 
 bi (Font_String)

libs/ui/font.c

@@ -36,6 +36,8 @@
 #include "QF/sys.h"
 #include "QF/math/bitop.h"
 
+#include "QF/plugin/vid_render.h"
+
 #include "QF/ui/font.h"
 
 #include "compat.h"
@@ -131,6 +133,7 @@ Font_Load (QFile *font_file, int size)
 
 		copy_glyph (rect, slot, font);
 	}
+	font->fontid = r_funcs->Draw_AddFont (font);
 
 	return font;
 }

libs/ui/text.c

@@ -165,6 +165,7 @@ Text_View (font_t *font, passage_t *passage)
 					.glyphid = glyphid,
 					.x = xp + bearing[0],
 					.y = yp - bearing[1],
+					.fontid = font->fontid,
 				};
 				x += xa;
 				y += ya;