refs: factor delete_ref loose ref step into a helper
refs: factor delete_ref loose ref step into a helper

Factor loose ref deletion into helper function delete_ref_loose to allow
later use elsewhere.

Signed-off-by: Brad King <91bf949d73a8f744e55949ef56efa0d05cf88599@kitware.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git