arm: dts: vexpress: Fix motherboard bus 'interrupt-map'

Commit 078fb7aa ("arm: dts: vexpress: Fix addressing issues with
'motherboard-bus' nodes") broke booting on a couple of 32-bit VExpress
boards. The problem is #address-cells size changed, but interrupt-map
was not updated. This results in the timer interrupt (and all the
other motherboard interrupts) not getting mapped.

As the 'interrupt-map' properties are all just duplicates across boards,
just move them into vexpress-v2m.dtsi and vexpress-v2m-rs1.dtsi.
Strictly speaking, 'interrupt-map' is dependent on the parent
interrupt controller, but it's not likely we'll ever have a different
parent than GICv2 on these old platforms. If there was one,
'interrupt-map' can still be overridden.

Link: https://lore.kernel.org/r/20210924214221.1877686-1-robh@kernel.org
Fixes: 078fb7aa

 ("arm: dts: vexpress: Fix addressing issues with 'motherboard-bus' nodes")
Cc: Guillaume Tucker <guillaume.tucker@collabora.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Reported-by: Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>