Revert "rustc-1.78.0 Build 11910258"

Revert submission 3108411-rust-update-prebuilts-1.78.0

Reason for revert: b/345708905

Reverted changes: /q/submissionid:3108411-rust-update-prebuilts-1.78.0

Change-Id: I66b95447ddfcb3d35e5f4305a6d9feb2896fbdf7
diff --git a/rust/config/global.go b/rust/config/global.go
index 6943467..e83e23a 100644
--- a/rust/config/global.go
+++ b/rust/config/global.go
@@ -24,7 +24,7 @@
 var (
 	pctx = android.NewPackageContext("android/soong/rust/config")
 
-	RustDefaultVersion = "1.78.0"
+	RustDefaultVersion = "1.77.1.p1"
 	RustDefaultBase    = "prebuilts/rust/"
 	DefaultEdition     = "2021"
 	Stdlibs            = []string{