ramips: 6.6: set testing kernel

Allow selecting 6.6 as testing kernel on ramips.

Signed-off-by: Mieczyslaw Nalewaj <[email protected]>

target/linux/ramips/Makefile

@@ -11,6 +11,7 @@ SUBTARGETS:=mt7620 mt7621 mt76x8 rt288x rt305x rt3883
 FEATURES:=squashfs gpio
 
 KERNEL_PATCHVER:=6.1
+KERNEL_TESTING_PATCHVER:=6.6
 
 define Target/Description
 	Build firmware images for Ralink RT288x/RT3xxx based boards.