android: Depend on gallium_dri from EGL, instead of linking in gallium.

The Android gallium build used to use gallium_egl, which was removed back
in March.  Instead, we will now use a normal Mesa libEGL loader with
dlopen()ing of a DRI module.

v2: add a clean step to rebuild all dri modules properly.
v3: Squish the 2 patches doing this together (change by anholt).

Signed-off-by: Chih-Wei Huang <cwhuang@linux.org.tw>
Reviewed-by: Eric Anholt <eric@anholt.net>
diff --git a/Android.mk b/Android.mk
index b19419b..6a09a9d 100644
--- a/Android.mk
+++ b/Android.mk
@@ -89,13 +89,9 @@
 	src/glsl \
 	src/mesa \
 	src/util \
-	src/egl/main
-
-ifeq ($(strip $(MESA_BUILD_CLASSIC)),true)
-SUBDIRS += \
+	src/egl/main \
 	src/egl/drivers/dri2 \
 	src/mesa/drivers/dri
-endif
 
 ifeq ($(strip $(MESA_BUILD_GALLIUM)),true)
 SUBDIRS += src/gallium