Unfortunately, I broke darwin with the last commit:

+ GOOS=darwin
+ GOARCH=amd64
+ go build -tags without_openssl -o /dev/null
../../../../pkg/mod/github.com/hanwen/go-fuse/v2@v2.1.1-0.20210825070001-74a933d6/fuse/server.go:122:5: undefined: parseFuseFd
../../../../pkg/mod/github.com/hanwen/go-fuse/v2@v2.1.1-0.20210825070001-74a933d6/fuse/server.go:887:5: undefined: parseFuseFd

Move parseFuseFd() to build on all archs to unbreak the build.

Change-Id: Ice173cc70a6a95765b56b444623b68ed92382052