egl/drivers: Convert to automake.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
diff --git a/configure.ac b/configure.ac
index 9cd814d..92f9b66 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1952,6 +1952,8 @@
 		src/gbm/Makefile
 		src/gbm/main/gbm.pc
 		src/egl/drivers/Makefile
+		src/egl/drivers/dri2/Makefile
+		src/egl/drivers/glx/Makefile
 		src/egl/main/Makefile
 		src/egl/main/egl.pc
 		src/egl/wayland/Makefile