Version bump to SP1A.210812.016.B1 [core/build_id.mk]

Change-Id: I83b63c5502e8d35a37a75f2be655a2faab1f4e50
diff --git a/core/build_id.mk b/core/build_id.mk
index 4b10232..cb659477 100644
--- a/core/build_id.mk
+++ b/core/build_id.mk
@@ -18,4 +18,4 @@
 # (like "CRB01").  It must be a single word, and is
 # capitalized by convention.
 
-BUILD_ID=SP1A.210812.016
+BUILD_ID=SP1A.210812.016.B1