MAINTAINERS: add MICROCHIP_FLEXCOM to at91

Add microchip flexcom driver to at91.
Signed-off-by: NEugen Hristev <eugen.hristev@microchip.com>

MAINTAINERS

@@ -246,6 +246,7 @@ S:	Maintained
 T:	git https://gitlab.denx.de/u-boot/custodians/u-boot-atmel.git
 F:	arch/arm/mach-at91/
 F:	board/atmel/
+F:	drivers/misc/microchip_flexcom.c
 
 ARM OWL
 M:	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>