Make static_executable an arch_variant

So that target executables can be static executables, and the same
module can make a host executable that isn't static.

Change-Id: Ibe0de001a8d1e7d59e617c244978098355718527
diff --git a/cc/cc.go b/cc/cc.go
index 43252f4..4cdcdf6 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -409,7 +409,7 @@
 
 type BinaryLinkerProperties struct {
 	// compile executable with -static
-	Static_executable *bool
+	Static_executable *bool `android:"arch_variant"`
 
 	// set the name of the output
 	Stem string `android:"arch_variant"`