Run additional compat checks for checkapi

They're already triggered by some other dependency for "full"
builds, but checkapi is expected to check all the APIs.

Test: m checkapi (with breaking change)
Change-Id: Ib9378bd6b6c43c7166309901f516c22e25e9ff4a

api/Android.mk

+.PHONY: checkapi
+checkapi: frameworks-base-api-current-compat frameworks-base-api-system-current-compat frameworks-base-api-module-lib-current-compat