Expose HostToolPath on the cc module to fix genrule.tool

Bug: 31742855
Test: Use `tool` in a genrule, ensure it runs properly.
Change-Id: Ib9ff35125edd66cdba8ede4f28aa6b753de0689b
diff --git a/cc/installer.go b/cc/installer.go
index fa8fc32..8ce9541 100644
--- a/cc/installer.go
+++ b/cc/installer.go
@@ -80,3 +80,7 @@
 func (installer *baseInstaller) inData() bool {
 	return installer.location == InstallInData
 }
+
+func (installer *baseInstaller) hostToolPath() android.OptionalPath {
+	return android.OptionalPath{}
+}