ipq807x: enable selecting 6.1 as testing kernel

Allow selecting 6.1 as the testing kernel on ipq807x.

Signed-off-by: Robert Marko <[email protected]>

target/linux/ipq807x/Makefile

@@ -9,6 +9,7 @@ CPU_TYPE:=cortex-a53
 SUBTARGETS:=generic
 
 KERNEL_PATCHVER:=5.15
+KERNEL_TESTING_PATCHVER:=6.1
 
 include $(INCLUDE_DIR)/target.mk
 DEFAULT_PACKAGES += \