configs/olpc_xo175_defconfig: bump kernel version to 5.8.2

Update kernel to version 5.8.2.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[Peter: explicitly select 5.8 headers]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/olpc_xo175_defconfig

@@ -1,12 +1,12 @@
 BR2_arm=y
 BR2_pj4=y
-BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_7=y
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_8=y
 BR2_ROOTFS_POST_BUILD_SCRIPT="board/olpc/post-build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
 BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/olpc/genimage.cfg"
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.7.1"
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.8.2"
 BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
 BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/olpc/xo-1.75/linux.config"
 BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="board/olpc/linux.config"