arch(draw): allow replacing the draw engine

BREAKING CHANGE: the API of lv_draw_... function have been changed

examples/libs/freetype/lv_example_freetype_1.c

@@ -1,5 +1,6 @@
 #include "../../lv_examples.h"
-#if LV_USE_FREETYPE && LV_BUILD_EXAMPLES
+#if LV_BUILD_EXAMPLES
+#if LV_USE_FREETYPE
 
 /**
  * Load a font with FreeType
@@ -42,3 +43,4 @@ void lv_example_freetype_1(void)
 }
 
 #endif
+#endif