Allow to disable asan on rust target

Test: Manual
Bug: 435759963
Flag: EXEMPT(build system)
Change-Id: I543b05c19912c225aa79bcb239d3d755ca8af755
diff --git a/rust/sanitize.go b/rust/sanitize.go
index af37261..60b8e62 100644
--- a/rust/sanitize.go
+++ b/rust/sanitize.go
@@ -48,7 +48,7 @@
 			// if set, enables sync memory tagging
 			Memtag_heap *bool `android:"arch_variant"`
 		}
-	}
+	} `android:"arch_variant"`
 	SanitizerEnabled bool `blueprint:"mutated"`
 
 	// Used when we need to place libraries in their own directory, such as ASAN.