Simplify rules for building renderer

Author: jserv

Makefile

@@ -60,14 +60,13 @@ libtwin.a_includes-y := \
 # Features
 libtwin.a_files-$(CONFIG_LOGGING) += src/log.c
 libtwin.a_files-$(CONFIG_CURSOR) += src/cursor.c
-libtwin.a_files-$(CONFIG_RENDERER_BUILTIN) += src/draw.c
 
-## Pixman
-libtwin.a_files-$(CONFIG_RENDERER_PIXMAN) += src/pixman.c
+# Renderer
+libtwin.a_files-$(CONFIG_RENDERER_BUILTIN) += src/draw.c
+libtwin.a_files-$(CONFIG_RENDERER_PIXMAN) += src/draw-pixman.c
 libtwin.a_cflags-$(CONFIG_RENDERER_PIXMAN) += $(shell pkg-config --cflags pixman-1)
 ifeq ($(CONFIG_RENDERER_PIXMAN), y)
 TARGET_LIBS += $(shell pkg-config --libs pixman-1)
-CFLAGS += $(shell pkg-config --cflags pixman-1)
 endif
 
 # Image loaders