Statically link missing libraries to libsurfaceflinger_unittest

Some targets do not have the library in their system or
vendor image so the test fails to run.

Fixes: 170341496
Test: atest -a libsurfaceflinger_unittest on cf_x86_64_phone-userdebug

Change-Id: I61e7702e6b36f218bebc7c87853001861a92741e
diff --git a/services/surfaceflinger/layerproto/Android.bp b/services/surfaceflinger/layerproto/Android.bp
index 0a73b23..e2a28a2 100644
--- a/services/surfaceflinger/layerproto/Android.bp
+++ b/services/surfaceflinger/layerproto/Android.bp
@@ -1,5 +1,5 @@
-cc_defaults {
-    name: "liblayers_proto_defaults",
+cc_library {
+    name: "liblayers_proto",
     export_include_dirs: ["include"],
 
     srcs: [
@@ -19,7 +19,7 @@
     proto: {
         export_proto_headers: true,
     },
-    
+
     cppflags: [
         "-Werror",
         "-Wno-unused-parameter",
@@ -35,20 +35,6 @@
     ],
 }
 
-cc_library_shared {
-    name: "liblayers_proto",
-    defaults: [
-        "liblayers_proto_defaults",
-    ],
-}
-
-cc_library_static {
-    name: "liblayers_proto_static",
-    defaults: [
-        "liblayers_proto_defaults",
-    ],
-}
-
 java_library_static {
     name: "layersprotosnano",
     host_supported: true,