pistachio: add 6.12 testing kernel

Allow selecting 6.12 as testing kernel on pistachio.

Runtime-tested:
 - Creator Ci40 Marduk 02KZ/5+

Signed-off-by: Zoltan HERPAI <[email protected]>

target/linux/pistachio/Makefile

@@ -13,6 +13,7 @@ CPU_SUBTYPE:=24kf
 SUBTARGETS:=generic
 
 KERNEL_PATCHVER:=6.6
+KERNEL_TESTING_PATCHVER:=6.12
 
 include $(INCLUDE_DIR)/target.mk