kernel: Move to Linux v5.4.16-openpower1

PowerPC releated changes:

 powerpc/xive: Discard ESB load value when interrupt is invalid
 powerpc/mm/hash: Fix sharing context ids between kernel & userspace
 powerpc/archrandom: fix arch_get_random_seed_int()
 powerpc/kasan: Fix boot failure with RELOCATABLE && FSL_BOOKE
 powerpc/pseries: Enable support for ibm,drc-info property
 powerpc/security: Fix debugfs data leak on 32-bit

Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/openpower/configs/witherspoon_defconfig b/openpower/configs/witherspoon_defconfig
index 0cce29d..b67cb3f 100644
--- a/openpower/configs/witherspoon_defconfig
+++ b/openpower/configs/witherspoon_defconfig
@@ -16,7 +16,7 @@
 BR2_ROOTFS_POST_BUILD_SCRIPT="../openpower/scripts/fixup-target-var ../openpower/scripts/firmware-whitelist"
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.4.13"
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.4.16"
 BR2_LINUX_KERNEL_PATCH="$(BR2_EXTERNAL_OP_BUILD_PATH)/linux"
 BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
 BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="$(BR2_EXTERNAL_OP_BUILD_PATH)/configs/linux/skiroot_defconfig"