ARM: HYP/non-sec: Make variable gic_dist_addr as a local one

Defining variable gic_dist_addr as a globe one prevents some
functions, which use it, from being used before relocation
which is the case in the deep sleep resume process on Freescale
SoC platforms.
Besides, we can always get the GIC base address by calling
get_gicd_base_address() without referring gic_dist_addr.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>