x86/mm/tlb: Revert the recent lazy TLB patches

x86/mm/tlb: Revert the recent lazy TLB patches

Revert commits:

  e8dfad19b120 x86/mm/tlb: Always use lazy TLB mode
  e3acc70ece19 x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs
  c90e7053388d x86/mm/tlb: Make lazy TLB mode lazier
  83f85ce4fbbb x86/mm/tlb: Restructure switch_mm_irqs_off()
  5b08dcdd40d1 x86/mm/tlb: Leave lazy TLB mode at page table free time

In order to simplify the TLB invalidate fixes for x86 and unify the
parts that need backporting.  We'll try again later.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>