x86: use kernel 6.12 by default

Switch to Linux kernel version 6.12.

Signed-off-by: Mieczyslaw Nalewaj <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/18848
Signed-off-by: Robert Marko <[email protected]>

target/linux/x86/Makefile

@@ -10,8 +10,7 @@ BOARDNAME:=x86
 FEATURES:=squashfs ext4 vdi vmdk vhdx pcmcia targz fpu boot-part rootfs-part
 SUBTARGETS:=generic legacy geode 64
 
-KERNEL_PATCHVER:=6.6
-KERNEL_TESTING_PATCHVER:=6.12
+KERNEL_PATCHVER:=6.12
 
 KERNELNAME:=bzImage