Rename ccConfig to cc_config

Follow up from aosp/1413495 to set a consistent name throughout the
package.

Test: m
Change-Id: Idafcd973e7d874cd97599ac419c2972a8a5cd0b4
diff --git a/rust/config/x86_darwin_host.go b/rust/config/x86_darwin_host.go
index 4104400..a13a9a6 100644
--- a/rust/config/x86_darwin_host.go
+++ b/rust/config/x86_darwin_host.go
@@ -23,7 +23,7 @@
 var (
 	DarwinRustFlags     = []string{}
 	DarwinRustLinkFlags = []string{
-		"-B${ccConfig.MacToolPath}",
+		"-B${cc_config.MacToolPath}",
 	}
 	darwinX8664Rustflags = []string{}
 	darwinX8664Linkflags = []string{}