MAINTAINERS: Update DTS path for ARM/Microchip (AT91) SoC

MAINTAINERS: Update DTS path for ARM/Microchip (AT91) SoC

Update the path to the supported DTS files for ARM/Microchip (AT91)
SoC to ensure that the output of the get_maintainer.pl script includes
the email addresses of the maintainers for all files located in
arch/arm/boot/dts/microchip.

Suggested-by: Conor Dooley <conor@kernel.org>
Signed-off-by: Andrei Simion <andrei.simion@microchip.com>
Reviewed-by: Cristian Birsan <cristian.birsan@microchip.com>
Link: https://lore.kernel.org/r/20240731144100.182221-1-andrei.simion@microchip.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>