drm_hwcomposer: Define cc_defaults for hwc3 binary

Some vendors do not use gralloc4 and can't use the BufferInfoGetter
implemented on top of the IMapper 4 API. These vendors use a
LegacyBufferInfoGetter implementation, and need to define a new build
target for it.

Move the majority of the configuration for the hwc3 service to a
cc_defaults target, so that this can be referenced downstream and reduce
duplication.

Change-Id: I2561ecbb2d3c520f8cd8bdbf171a28d5f7fb1a51
Signed-off-by: Drew Davenport <ddavenport@google.com>

Android.bp

diff --git a/Android.bp b/Android.bp
index f358265..d6994ac 100644
--- a/Android.bp
+++ b/Android.bp
@@ -163,14 +163,13 @@
     ],
 }
 
-cc_binary {
-    name: "android.hardware.composer.hwc3-service.drm",
+cc_defaults {
+    name: "android.hardware.composer.hwc3-service.drm.defaults",
 
     srcs: [
         ":drm_hwcomposer_common",
         ":drm_hwcomposer_hwc3",
         ":drm_hwcomposer_service",
-        "bufferinfo/legacy/BufferInfoLibdrm.cpp",
     ],
 
     defaults: [
@@ -186,16 +185,25 @@
     ],
 
     cflags: [
+        "-DUSE_IMAPPER4_METADATA_API",
         "-Wall",
         "-Werror",
-
-        "-DUSE_IMAPPER4_METADATA_API",
     ],
 
     cppflags: [
         "-DHWC2_INCLUDE_STRINGIFICATION",
         "-DHWC2_USE_CPP11",
     ],
+}
+
+cc_binary {
+    name: "android.hardware.composer.hwc3-service.drm",
+
+    defaults: [
+        "android.hardware.composer.hwc3-service.drm.defaults",
+    ],
+
+    srcs: ["bufferinfo/legacy/BufferInfoLibdrm.cpp"],
 
     relative_install_path: "hw",
     vendor: true,