Add "renesas,irqc-r8a7791" to the compatible string for IRQC
in case of r8a7791. This makes the IRQC follow the same style
as the other devices and also makes it more future proof.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>