clang now supports -fdebug-prefix-map=.

Soong port of https://android-review.googlesource.com/204111

Change-Id: Id0569831f09845871d8e6990c310516bea5a2510
diff --git a/cc/clang.go b/cc/clang.go
index 5e0302a..df7ec01 100644
--- a/cc/clang.go
+++ b/cc/clang.go
@@ -31,7 +31,6 @@
 	"-Wunused-but-set-parameter",
 	"-Wunused-but-set-variable",
 	"-fdiagnostics-color",
-	"-fdebug-prefix-map=/proc/self/cwd=",
 
 	// arm + arm64 + mips + mips64
 	"-fgcse-after-reload",