[syslinux] Syncying and upstreaming 4k sector patches

[Frediano Ziglio]

Hi,
  time ago I started doing support for 4k sector disk for syslinux.

Patches worked for my cases (ext) and did not introduced regression
problems with normal disks. Now I would like to update these patches and
upstream them. It's not clear however which is the branch I should use
to rebase these patches. Previous patches was against syslinux-4.06 but
now there is syslinux-5.01 (elflink) and syslinux-6.00-pre4 (firmware).

Frediano