Revert "Disable LTO and CFI for riscv64"

This reverts commit ecf4e664e0.

Reason for revert: Not needed as emultated tls is now globally disabled https://android-review.git.corp.google.com/c/platform/build/soong/+/2431153

Change-Id: Idc3de2771afbbe2d5976f3c7974b3ffd15441b13

cc/sanitize.go

@@ -653,12 +653,6 @@ func (sanitize *sanitize) begin(ctx BaseModuleContext) {
 		s.Integer_overflow = nil
 	}
 
-	// TODO(b/254713216): CFI doesn't work for riscv64 yet because LTO doesn't work.
-	if ctx.Arch().ArchType == android.Riscv64 {
-		s.Cfi = nil
-		s.Diag.Cfi = nil
-	}
-
 	// Disable CFI for musl
 	if ctx.toolchain().Musl() {
 		s.Cfi = nil