drm_hwcomposer: Add platformmeson for Amlogic SoC support

This specific platform handler is dedicated for the Amlogic SoC,
and more precisely for the Amlogic G12A family.

OpenGL/Mali allocation is done via a slightly modified ARM Gralloc
module, thus needing a custom platform handler to handle the custom
private_handle_t structure.

This platformmeson is based on platformhisi without the AFBC YUV
management (not handled by the Amlogic SoCs).

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>

Change-Id: I1a1d20b0a84b0e17aa3417c8e9633712f258523d
diff --git a/Android.bp b/Android.bp
index 2af4548..cd28e41 100644
--- a/Android.bp
+++ b/Android.bp
@@ -110,3 +110,12 @@
         "platformhisi.cpp",
     ],
 }
+
+// Used by hwcomposer.drm_meson
+filegroup {
+    name: "drm_hwcomposer_platformmeson",
+    srcs: [
+        "platformdrmgeneric.cpp",
+        "platformmeson.cpp",
+    ],
+}