app: aboot: Define helper functions for AVB 2.0

Define functions for critical lock and enforcing
verity for AVB 2.0.

Change-Id: I02f4289ded6faefb5ba549074cbba837eb653f86
diff --git a/include/platform.h b/include/platform.h
index bce5970..b33399d 100644
--- a/include/platform.h
+++ b/include/platform.h
@@ -100,4 +100,6 @@
 int get_userkey(uint8_t **user_key, uint32_t *user_key_size);
 int erase_userkey();
 int store_userkey(uint8_t *user_key, uint32_t user_key_size);
+bool is_device_locked_critical();
+bool is_verity_enforcing();
 #endif