Revert^2 "Add soong config variable Release_expose_flagged_api"

This reverts commit 5548bf305368571c40461a818f24f26cbe2de533.

Test: m nothing
Bug: 299570421
Change-Id: I9f70648fb6657bbf4f5681cd6d40517d70a8fefb
diff --git a/android/variable.go b/android/variable.go
index 44a8fd7..d4cd863 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -490,6 +490,8 @@
 	PartitionVarsForBazelMigrationOnlyDoNotUse PartitionVariables `json:",omitempty"`
 
 	NextReleaseHideFlaggedApi *bool `json:",omitempty"`
+
+	Release_expose_flagged_api *bool `json:",omitempty"`
 }
 
 type PartitionVariables struct {