automake: rework the EGL build

Simplify things by merging the two makefiles. This way we can combine
the duplicated HAVE_PLATFORM_ checks, and build the library without
having a separate static library.

v2: use $() when referencing variables, use correct define (Matt)

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
diff --git a/src/Makefile.am b/src/Makefile.am
index 90bf947..0d49bcd 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -35,16 +35,12 @@
 SUBDIRS += egl/wayland/wayland-egl egl/wayland/wayland-drm
 endif
 
-if HAVE_EGL_DRIVER_DRI2
-SUBDIRS += egl/drivers/dri2
-endif
-
 if HAVE_GBM
 SUBDIRS += gbm
 endif
 
 if HAVE_EGL
-SUBDIRS += egl/main
+SUBDIRS += egl
 endif
 
 if HAVE_GALLIUM
@@ -52,8 +48,6 @@
 endif
 
 EXTRA_DIST = \
-	egl/drivers/haiku \
-	egl/docs \
 	getopt hgl SConscript
 
 AM_CFLAGS = $(VISIBILITY_CFLAGS)