ARM: S5P: Unify defines for both gpio interrupt types

Samsung S5P SoCs have the same interrupt type defines for both
external interrupts and gpio interrupts. This patch removes all
duplicates from S5PC100 and S5PV210 specific includes as well as
gpio interrupt code and put a common defines to plat/irqs.h
NOTE: Do not use this for S5P6440 and S5P6450.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[kgene.kim@samsung.com: add note for S5P64X0]
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>