s390 fixes:
 - Initialize timing related variables first and then enable the timer interrupt.
 - Normalize nano seconds to micro seconds in do_gettimeofday.
 - Add types for __kernel_timer_t and __kernel_clockid_t.
 - Fix ugly bug in switch_to: set prev to the return value of resume, otherwise
   prev still contains the previous process at the time resume was called and
   not the previous process at the time resume returned. They differ...
 - Add missing include to get the kernel compiled.
 - Get a closer match with the i386 termios.h file.
 - Cope with INITIAL_JIFFIES.
 - Define cpu_relax to do a cpu yield on VM and LPAR.
 - Don't reenable interrupts in program check handler.
 - Add pte_file definitions.
 - Fix PT_IEEE_IP special case in ptrace.
 - Use compare and swap to release the lock in _raw_spin_unlock.
 - Introduce invoke_softirq to switch to async. interrupt stack.