[coreboot] romcc -mcpu=p3?

[Andriy Gapon]

It seems that romcc with -mcpu=p3 -O produces incorrect code for 
cpu/x86/16bit/reset16.inc. -mpcu=p2 -O does work fine.

I will try to provide more hard data later but it looks like the 
following code is compiled into an (slightly) incorrect jump which 
breaks things terribly, of course.
  .section ".reset"
  .code16
.globl reset_vector
reset_vector:
  .byte 0xe9
  .int _start - ( . + 2 )
  . = 0x8;
  .code32

Jump seems to be off by -4 bytes.