graphics: add IComposer service daemon

Since HALs might run binder services, we need to start thread pool for
both binder and hwbinder.

Bug: 32021609
Test: builds and boots
Change-Id: I9779e86b1e611a180b1984af36c417dafc3329bc
diff --git a/graphics/composer/2.1/default/android.hardware.graphics.composer@2.1-service.rc b/graphics/composer/2.1/default/android.hardware.graphics.composer@2.1-service.rc
new file mode 100644
index 0000000..fc21d59
--- /dev/null
+++ b/graphics/composer/2.1/default/android.hardware.graphics.composer@2.1-service.rc
@@ -0,0 +1,5 @@
+service hwcomposer-2-1 /system/bin/hw/android.hardware.graphics.composer@2.1-service
+    class hal
+    user system
+    group graphics drmrpc readproc
+    onrestart restart surfaceflinger