[PATCH] x86-64 architecture specific sync for 2.5.8

[PATCH] x86-64 architecture specific sync for 2.5.8

This patch brings 2.5.8 in sync with the x86-64 2.4 development tree again
(excluding device drivers)

It has lots of bug fixes and enhancements. It only touches architecture
specific files.

- Sync with 2.5.8
- SMP/APIC supported now.
- Module loading works now.
- Time keeping bugs fixed.
- entry.S streamlined and some bugs fixed.
- modify_ldt works now
- mostly rewritten FPU support (including FXRSTOR for initial FPU
  initialization based on the initial state)
- 32bit emulation enhanced and bugs fixed.
- rewrote mm initialization and lots of cleanups in the page table handling
  __PAGE_OFFSET is now moved to 0x10000000000 and some vmalloc/ioremap
  problems have been fixed. They have an own PML4 slot now.
- WCHAN reporting support for RIP (but not RSP)
- Lots of various other bug fixes and cleanups.

Currently broken:
- ACPI
- MTRR

It needs some other bugfixes outside architecture specific code. I sent
them all in separate mail.