squisher: Fix naming of zips for devices with _ in name

Change-Id: Iac908954a435f275f606e99c4282ac4f5aacb9a3
Example: umts_spyder comes out as Gummy-M.1-02-07-14-NIGHTLY-umts.zip
Merge branch 'kitkat' of https://github.com/LiquidSmooth/android_vendor_liquid into kitkat