[syslinux] Updated status on UEFI compliant version of the pxechn-module

[Patrick Masotta]

>>> I'd like to get UEFI chaining working first.

<<<
I have sent in the past two patches; one allows SL to chainload to efi executives and the other one 
allows to link the gnu-efi layer to a com32 module in order to access the EFI firmware from the com32 code.
Despite minor changes I might've made during all this time that code works...
Best,Patrick