ARM: shmobile: sh73a0: fixup RELOC_BASE of intca_irq_pins_desc

sh73a0 :: intca_irq_pins_desc irq table had conflict
from irq 552 to irq 557 before.
But the second controller was simply trampling the
first one by way of the -EEXIST case from irq_alloc_desc_at().

But now, we have irqdomain support from
1d6a21b0
(sh: intc: initial irqdomain support)

The irqdomain code has simply tightened down the sanity checks and
error path. So, sh73a0 CPU board got some WARNING when booting now.
This patch fixup RELOC_BASE to solve this issue.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>