ramips/rt305x: Name DTS files based on scheme

target/linux/ramips/dts/rt3050_8devices_carambola.dts

target/linux/ramips/dts/rt3050_allnet_all0256n-4m.dts

target/linux/ramips/dts/rt3050_allnet_all0256n-8m.dts

target/linux/ramips/dts/rt3050_allnet_all0256n.dtsi

...et/linux/ramips/dts/rt3050_alphanetworks_asl26555-16m.dts

target/linux/ramips/dts/rt3050_alphanetworks_asl26555-8m.dts

target/linux/ramips/dts/rt3050_alphanetworks_asl26555.dtsi

target/linux/ramips/dts/rt3050_arcwireless_freestation5.dts

target/linux/ramips/dts/rt3050_asus_rt-g32-b1.dts

target/linux/ramips/dts/rt3050_asus_rt-n10-plus.dts

target/linux/ramips/dts/rt3050_asus_wl-330n.dts

target/linux/ramips/dts/rt3050_asus_wl-330n3g.dts

target/linux/ramips/dts/rt3050_dlink_dcs-930.dts

target/linux/ramips/dts/rt3050_dlink_dir-300-b1.dts

target/linux/ramips/dts/rt3050_dlink_dir-600-b1.dts

target/linux/ramips/dts/rt3050_dlink_dir-615-d.dts

target/linux/ramips/dts/rt3050_dlink_dir-620-a1.dts

target/linux/ramips/dts/rt3050_edimax_3g-6200n.dts

target/linux/ramips/dts/rt3050_edimax_3g-6200nl.dts

target/linux/ramips/dts/rt3050_huawei_d105.dts