ARM: dts: koelsch: Stop building r8a7791-koelsch.dtb in legacy builds

Koelsch is no longer supported in legacy builds.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/Makefile

@@ -384,7 +384,6 @@ dtb-$(CONFIG_ARCH_SHMOBILE_LEGACY) += \
 	r8a7778-bockw-reference.dtb \
 	r8a7779-marzen.dtb \
 	r8a7790-lager.dtb \
-	r8a7791-koelsch.dtb \
 	sh7372-mackerel.dtb \
 	sh73a0-kzm9g.dtb \
 	sh73a0-kzm9g-reference.dtb