Revert "Switch to llvm-ar (with crsD flags only)."

This reverts commit 13bc31d6e180b7fd52e82d3013c5d6da57fd8c24.

Bug: 71694982
Reason for revert: Broke Mac build

Change-Id: I0da6866442ca9273dd329f0b82932f939b7f65ed
diff --git a/cc/builder.go b/cc/builder.go
index a280ec5..de85d6e 100644
--- a/cc/builder.go
+++ b/cc/builder.go
@@ -508,8 +508,8 @@
 		return
 	}
 
-	arCmd := "${config.ClangBin}/llvm-ar"
-	arFlags := "crsD"
+	arCmd := gccCmd(flags.toolchain, "ar")
+	arFlags := "crsPD"
 	if flags.arFlags != "" {
 		arFlags += " " + flags.arFlags
 	}