ARM: dts: Fix elm interrupt compiler warning

[ Upstream commit d364b038 ]

Looks like the interrupt property is missing the controller and level
information causing:

Warning (interrupts_property): interrupts size is (4), expected multiple
of 12 in /ocp/elm@48078000

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>