tests: only check the size in dl-linux-tarball.bash
tests: only check the size in dl-linux-tarball.bash

Getting rid of the MD5 calculation makes calling the script
virtually free, where it took 0.2 seconds before.

rfjakob/gocryptfs,davesteele/gocryptfs,davesteele/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs,davesteele/gocryptfs