arm64: dts: zx: Fix gic GICR property

GICR for multiple CPU can be described with start address and stride,
or with multiple address. Current multiple address and stride are
both used. Fix it.

vmalloc patch 727a7f5a9 triggered this bug:
[    0.097146] Unable to handle kernel paging request at virtual address ffff000008060008
[    0.097150] pgd = ffff000008602000
[    0.097160] [ffff000008060008] *pgd=000000007fffe003, *pud=000000007fffd003, *pmd=000000007fffc003, *pte=0000000000000000
[    0.097165] Internal error: Oops: 96000007 [#1] PREEMPT SMP
[    0.097170] Modules linked in:
[    0.097177] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0+ #1474
[    0.097179] Hardware name: ZTE zx296718 evaluation board (DT)
[    0.097183] task: ffff80003e8c8b80 task.stack: ffff80003e8d0000
[    0.097197] PC is at gic_populate_rdist+0x74/0x15c
[    0.097202] LR is at gic_starting_cpu+0xc/0x20
[    0.097206] pc : [<ffff0000082b1b18>] lr : [<ffff0000082b26e0>] pstate: 600001c5

Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>