[Bug go/84484] libgo configure tests fail to find -latomic

[ian at airs dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84484

--- Comment #1 from Ian Lance Taylor <ian at airs dot com> ---
Does the patch in https://golang.org/cl/95436 fix the problem?

Note that there will be other problems building libgo for riscv: it will need
to be added to goarch.sh, match.sh, and testsuite/gotest, and a bunch of files
will need build constraints added.