mediatek: remove duplicate dts-v1 statement for UniFi 6 LR

/dts-v1/; must only be specified once.

Fixes: e887049fbb74 ("mediatek: add alternative bootchain variant
for UniFi 6 LR")

Signed-off-by: Adrian Schmutzler <[email protected]>

target/linux/mediatek/dts/mt7622-ubnt-unifi-6-lr-ubootmod.dts

@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later OR MIT
 
-/dts-v1/;
 #include "mt7622-ubnt-unifi-6-lr.dtsi"
 
 / {

target/linux/mediatek/dts/mt7622-ubnt-unifi-6-lr.dts

@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later OR MIT
 
-/dts-v1/;
 #include "mt7622-ubnt-unifi-6-lr.dtsi"
 
 / {