check ARCHVERSION for hyphen before creating localversion

If hyphen doesn't exist in uname -r (ARCHVERSION), then it is probably a
non-distro kernel and we don't need to create the localversion file.

Fixes #376

Signed-off-by: Seth Jennings <sjenning@redhat.com>
Merge pull request #417 from spartacus06/fix-376

check ARCHVERSION for hyphen before creating localversion