tzcode-native: Fix SRC_URI checksum typo

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
dropbear: use pidfile for daemon start/stop/restart

Old init script killed all dropbear processes when doing stop/restart
including open SSH sessions which is very annoying.

Signed-off-by: Roman I Khimov <khimov@altell.ru>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>