support/testing: test_xfsprogs: use bootlin toolchain, update kernel

This commit updates the test configuration to switch to a Bootlin
external toolchain. This is needed to get newer toolchain kernel
headers required by newer xfsprogs versions.

xfsprogs upstream commit [1] (included in v6.15) introduced a usage
of the "capacity" field of zoned block devices, introduced in Kernel
commit [2], first included in v5.9.

This commit also updates the runtime test Kernel version
to the LTS 6.18.18. This is because the default filesystem options
of mkfs.xfs were updated in upstream commit [3] to include new
features supported in the new Kernel 6.18.y LTS series. The commit [3]
is included in xfsprogs v6.18.

[1] https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git/commit/?id=48ccc2459039309cfbaf358febea53a86f07827c
[2] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=82394db7383d33641f3f565bd79792fb41b1741f
[3] https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git/commit/?id=54aad16b4b9b923442b4042afaba4438ca1aa868

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Romain Naour <romain.naour@smile.fr>
(cherry picked from commit c03712d8ec)
Signed-off-by: Thomas Perale <thomas.perale@mind.be>

support/testing/tests/package/test_xfsprogs.py

@@ -12,10 +12,11 @@ class TestXfsProgs(infra.basetest.BRTest):
         f"""
         BR2_aarch64=y
         BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
         BR2_TARGET_GENERIC_GETTY_PORT="ttyAMA0"
         BR2_LINUX_KERNEL=y
         BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-        BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.6.37"
+        BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.18.18"
         BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
         BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/qemu/aarch64-virt/linux.config"
         BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="{kern_frag}"