If just one multiboot kernel module was loaded after bender, the
relocation was skipped before. This resulted in a corrupt binary image
on ELF loading if the regions of the boot module and the final program
overlap. Now, all modules are copied below 2 GiB (and out of the way)
before ELF loading.
Fixes#1624
Bender upstream issue is TUD-OS/morbo#4
'Bender' can detect serial ports accessible via PCI and writes the I/O ports
to the Bios Data area (BDA).
Usage together with the PXE bootloader ease life running Genode/NOVA on native
hardware, where a standard serial device isn't available anymore anywhere.
