Add min_sdk_version:R to updatable apexes

APEXes introduced in R need to set min_sdk_version to ensure that they
are built against correct version of stubs (libc/liblog/...).

Bug: 152655956
Test: m
Merged-In: Id3f94a2ac09bd7bf7f9a4a0c2f62b624f29509d0
Change-Id: Id3f94a2ac09bd7bf7f9a4a0c2f62b624f29509d0
(cherry picked from commit ab9dfa4321)

adb/apex/Android.bp

@@ -1,6 +1,7 @@
 apex_defaults {
     name: "com.android.adbd-defaults",
     updatable: true,
+    min_sdk_version: "R",
 
     binaries: ["adbd"],
     compile_multilib: "both",