[LIBS] netstack: Added NETSTACK_IPRIORITY define for modules using net stack

Modules using network stack should have IPRIORITY greater than NETSTACK_IPRIORITY.

Signed-off-by: Anup Patel <anup@brainfault.org>
[ARM] Exynos4: Add code to help determine the SOC type.

Signed-off-by: Anup Patel <anup@brainfault.org>
[ARM] Exynos4: remove motherboard.h header file

Signed-off-by: Anup Patel <anup@brainfault.org>
Merge remote-tracking branch 'upstream/master' into dev_exynos4