build-without-openssl.bash also disables CGO, so
this makes it more real-world-y.
But the real reason is that disabling CGO hopefully
fixes this travis ci build failure:
+GOOS=darwin
+GOARCH=arm64
+go build -tags without_openssl
/home/travis/.gimme/versions/go1.13.15.linux.amd64/pkg/tool/linux_amd64/link: running gcc failed: exit status 1
/usr/bin/ld: unrecognized option '-pagezero_size'
/usr/bin/ld: use the --help option for usage information
collect2: error: ld returned 1 exit status
The command "./crossbuild.bash" exited with 2.
From https://github.com/golang/go/wiki/GoArm :
In cross compilation situations, it is recommended
that you always set an appropriate GOARM value
along with GOARCH.
The value seems to default to GOARM=5 if not set
during cross-compilation.
