Samsung Galaxy S5 klte: move downstream port to unmaintained
Move downstream port to unmaintained. While doing so, refactor firmware package and get rid of unused custom scripts and hacks.
- firmware-samsung-klte: split wifi and bt firmware
- downstream port: depend only on wifi firmware, remove unsued scripts, remove dropbear sshd workaround
- main port: use only mainline kernel, depend on both bt & wifi firmware, depend on swclock-offset, cleanup and tidy up apkbuild