lantiq: set Linux 6.1 as testing kernel

Add KERNEL_TESTING_PATCHVER for Linux 6.1.

Signed-off-by: Martin Schiller <[email protected]>

target/linux/lantiq/Makefile

@@ -10,6 +10,7 @@ FEATURES:=squashfs
 SUBTARGETS:=xrx200 xway xway_legacy falcon ase
 
 KERNEL_PATCHVER:=5.15
+KERNEL_TESTING_PATCHVER:=6.1
 
 define Target/Description
 	Build firmware images for Lantiq SoC