starfive: use kernel 6.12 by default

Switch to Linux kernel version 6.12.

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

target/linux/starfive/Makefile

@@ -10,8 +10,7 @@ BOARDNAME:=StarFive JH71x0 (7100/7110)
 FEATURES:=ext4
 KERNELNAME:=Image dtbs
 
-KERNEL_PATCHVER:=6.6
-KERNEL_TESTING_PATCHVER:=6.12
+KERNEL_PATCHVER:=6.12
 
 include $(INCLUDE_DIR)/target.mk