Fix do_page_fault and update_mmu_cache.

  * Fix do_page_fault (vmalloc_fault:) to pass error_code correctly
    to update_mmu_cache by using a thread-fault code for all m32r chips.

  * Fix update_mmu_cache for OPSP chip
    - #ifdef CONFIG_CHIP_OPSP portion is a workaround of OPSP;
      Add a notfound-case operation to update_mmu_cache for OPSP
      like other m32r chip.
    - Fix pte_data that was not initialized if no entry found.

Signed-off-by: Kazuhiro Inaoka <inaoka@linux-m32r.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>