malta: enable 6.18 testing kernel

The malta now supports 6.18 kernel as testing.

Signed-off-by: Mieczyslaw Nalewaj <namiltd@yahoo.com>
Link: openwrt/openwrt#20965
Signed-off-by: Robert Marko <robimarko@gmail.com>

Author: namiltd

target/linux/malta/Makefile

@@ -11,6 +11,7 @@ INITRAMFS_EXTRA_FILES:=
 FEATURES:=cpiogz ext4 ramdisk squashfs targz
 
 KERNEL_PATCHVER:=6.12
+KERNEL_TESTING_PATCHVER:=6.18
 
 include $(INCLUDE_DIR)/target.mk