extlinux-update sorts kernels in the wrong order due to not using sort -Vr, fixed upstream

[Carey Underwood]

extlinux-update contains the line _VERSIONS="$(cd /boot && ls vmlinuz-* | grep -v .dpkg-tmp | sed -e 's|vmlinuz-||g' | sort -nr)", which attempts to sort on version numbers numerically. The problem is that in kernel version numbers, 3.10 comes after 3.9, while sort -n will sort it before (as 3.10 is numerically lower than 3.90 or 3.9).

Debian has already fixed it to use the version sort (sort -Vr).

I think this is worth an SRU as it causes 3.10+ kernels to not be booted while any 3.2-3.9 kernels are installed.