Update clang prebuilt lib paths

Necessary to update the platform to newer clang.

Bug: 248422209
Test: forest
Change-Id: I43e0835c4250e6d4dd78928bc19d6e80470fb060
diff --git a/build/makevars.go b/build/makevars.go
index 1965b5d..0606bab 100644
--- a/build/makevars.go
+++ b/build/makevars.go
@@ -34,6 +34,7 @@
 		"bin/llvm-addr2line",
 		"bin/llvm-dwarfdump",
 		"bin/llvm-objdump",
+		"lib/libc++.so.1",
 		"lib64/libc++.so.1",
 	}
 )