Add H3B DDR init sequence

This doesn't get used anywhere (yet) but it does pass
some cursory testing, if anyone is interested.

Signed-off-by: evilwombat <evilwombat@server.fake>
Add support for LEDs and sdcard slot in Linux

Add kernel support for the Hero2 LEDs and sdcard slot, and
enable the corresponding features. Add patch files and
update prebuilt kernel.

Signed-off-by: evilwombat <evilwombat@server.fake>