Add avb app to userspace library build system

Switch to building avb with the trusted_app.mk system instead of as a
generic lk module. This allows the app to depend on common userspace
static libraries.

Test: build.py qemu-generic-arm64-test-debug
Bug: 169448829
Change-Id: I97dd91cdbd7de667f16a1b3eb9179bbe064827d1
diff --git a/rules.mk b/rules.mk
index a2ad7f9..1f19e4e 100644
--- a/rules.mk
+++ b/rules.mk
@@ -28,7 +28,7 @@
 
 IPC := ipc
 
-MODULE_DEPS += \
+MODULE_LIBRARY_DEPS += \
 	trusty/user/base/lib/libc-trusty \
 	trusty/user/base/lib/libstdc++-trusty \
 	trusty/user/base/lib/storage \
@@ -41,5 +41,4 @@
 
 include $(LOCAL_DIR)/$(IPC)/rules.mk
 
-include make/module.mk
-
+include make/trusted_app.mk