cmd/go: insert goroot to the hash of build cache when the packages include C files
There are some absolute paths in the object file of the packages include C files. The path in C objects file can't be rewritten by linker. The goroot must be used as input for the hash when the packages include C files. So that the debug_info of the binary is correctly.
Fixes #48319
Change-Id: I659a3d6d71c4e49fff83f5bcf53a0a417e552a93
Reviewed-on: https://go-review.googlesource.com/c/go/+/348991 Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Meng Zhuo <mzh@golangcn.org>
Trust: Jay Conrod <jayconrod@google.com>