Host builds: add fastboot and adb

Add fastboot and adb host utilities to debug builds for debugging
and development purposes.

Change-Id: If77699a27497b8641998930f14d4ee418b856080
One less warning

Change-Id: Icdf2608c9ddda1cae846cd1ff4e66058fdabbcfb
core: Improve LPM support

 * Larger last_kmsg buffer in the charger log for debugging.
 * Load /init.lpm.rc in order to externalize charger setup.
 * Add support for Samsung's LPM reset reason.

Change-Id: I38cd63f7aa05685d2075d2568faf2f94f8440c88