board: ti: am57xx: Add dt support for BeagleBoard-X15 revC

Add support for selecting proper dtb for
am57xx BeagleBoard X15 revC u-boot from FIT

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index fdb1cbe..1d6cee2 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -176,6 +176,7 @@
 	dra72-evm-revc.dtb dra71-evm.dtb dra76-evm.dtb
 dtb-$(CONFIG_TARGET_AM57XX_EVM) += am57xx-beagle-x15.dtb \
 	am57xx-beagle-x15-revb1.dtb \
+	am57xx-beagle-x15-revc.dtb \
 	am572x-idk.dtb	\
 	am571x-idk.dtb
 dtb-$(CONFIG_TARGET_STV0991) += stv0991.dtb