[all] Add define:  device_target_cpu: Used for native builds. Normally the nested droid build env will do an old-fashioned cross-compile and produce non-x86 binaries (default armv7hl). This can be set to tell OBS what arch the binaries are. Eg Android for Intel arch must set this.

Signed-off-by: David Greaves <david.greaves@jolla.com>
[nuc] Add dhd for nuc