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The arm-gic.h was a concatenation of arm-gic.h and irq.h from Linux.
Just copy the 2 files here. They both have MIT license which is accepted
in TF-A.
With this alignment, a new macro is added (GIC_CPU_MASK_SIMPLE).
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Change-Id: Ib45174f35f1796ebb7f34af861b59810cfb808b0