biosemu (non-yabel) cleanup

biosemu (non-yabel) cleanup
* Drop pcbios folder that only exists for a single function
* include int1a handler in biosemu.c
* Wipe a lot of dead code, and set up F segment correctly
* include return value check from yabel.

On the long run we should teach yabel to be able to run with a reduced feature
set, ie. no emulation of (almost) all system hardware. Then we could drop the
non-yabel x86emu.
But for now this patch cleans up the non-yabel biosemu.c to a state where it's
not all that ugly anymore..

Signed-off-by: Stefan Reinauer <stepan@coresystems.de>
Acked-by: Myles Watson <mylesgw@gmail.com>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4915 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1