Reland "Make DWARF v5 the default debug information format."

This reverts commit bb1a17aecb1d8b11f15a29d2578cd14a24e9c622.

Bug: http://b/182004844
Bug: http://b/195152239
Bug: http://b/195698910
Test: Builds

Change-Id: I6f84bd7e0f2a26799de2d6b9db4abe5d3dc968be
diff --git a/cc/config/global.go b/cc/config/global.go
index e46ac96..5acc7f5 100644
--- a/cc/config/global.go
+++ b/cc/config/global.go
@@ -46,6 +46,7 @@
 
 		"-O2",
 		"-g",
+		"-fdebug-default-version=5",
 
 		"-fno-strict-aliasing",