Minimal iPXE build

[NiKiZe]

Some documentation for selecting drivers: http://ipxe.org/appnote/buildtargets

if you just want it small use the snponly.efi build which should work on all devices that already have network boot support and provides SNP/NII driver.

If you actually need multiple drivers then build via the intel--rtl8169--snp.efi syntax.

for only intel you will just build with intel.efi