From: Andi Kleen <ak@suse.de>

Fix a few issues on x86-64 for 2.6.4rc1.

The 32bit emulation used 4GB/3 for the mmap break. This actually gave
programs less sbrk space than with a standard 32bit kernel. Move the 32bit
mmap break to 0xc5000000.

Uses the correct gcc option to optimize for Prescott now (requires a very
new mainline gcc)

Also merge the i386 sched_clock().  I hope this will fix some interactivity
problems with the scheduler.

- Change initializer to new style (Arnd Bergmann)
- Remove 2 sibling limit in HT support (from i386)
- Always log RIP in MCE records even when not exact
- Move 32bit program task break up to 0xc5000000 by default
- Use -march=prescott for Prescott optimized kernel if possible
- Don't divide by zero with report_lost_ticks on and HPET off
- Merge preempt/smp/debug_pagealloc oops printing from i386
- Add pfn_to_nid()
- Merge more accurate sched_clock from i386
- Remove traces of debugging code in mce.c
- Update defconfig