configs/qemu_arm_{versatile, vexpress}_defconfig: update devicetree path

The last kernel version bump broke qemu ARM defconfigs [1] since
all devicetree where moved to to vendor sub-directories in 6.5 [2].

[1] 9982e0b5a6 ("configs/qemu: update defconfigs to Linux 6.6.18")
[2] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=724ba6751532055db75992fc6ae21c3e322e94a7

Fixes:
https://gitlab.com/buildroot.org/buildroot/-/jobs/6655119888 (qemu_arm_versatile_defconfig)
https://gitlab.com/buildroot.org/buildroot/-/jobs/6655119890 (qemu_arm_vexpress_defconfig)

Reported-by: Waldemar Brodkorb on IRC
Cc: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Romain Naour <romain.naour@smile.fr>

configs/qemu_arm_versatile_defconfig

@@ -24,7 +24,7 @@ BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.6.18"
 BR2_LINUX_KERNEL_DEFCONFIG="versatile"
 BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="board/qemu/arm-versatile/linux.fragment"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_INTREE_DTS_NAME="versatile-pb"
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="arm/versatile-pb"
 
 # host-qemu for gitlab testing
 BR2_PACKAGE_HOST_QEMU=y

configs/qemu_arm_vexpress_defconfig

@@ -28,7 +28,7 @@ BR2_LINUX_KERNEL_CUSTOM_VERSION=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.6.18"
 BR2_LINUX_KERNEL_DEFCONFIG="vexpress"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_INTREE_DTS_NAME="vexpress-v2p-ca9"
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="arm/vexpress-v2p-ca9"
 
 # host-qemu for gitlab testing
 BR2_PACKAGE_HOST_QEMU=y