raspberrypi_defconfig: bump to kernel version 4.4.8

Signed-off-by: Benoît Mauduit <bmauduit@beneth.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/raspberrypi_defconfig

@@ -12,7 +12,7 @@ BR2_TOOLCHAIN_BUILDROOT_CXX=y
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_GIT=y
 BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/raspberrypi/linux.git"
-BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="3de232825c9ba5989522b8691eb6ac5df6619458"
+BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="26f3b72a9c049be10e6af196252283e1f6ab9d1f"
 BR2_LINUX_KERNEL_DEFCONFIG="bcmrpi"
 
 # Build the DTBs for A/B, A+/B+ and compute module from the kernel sources