remove unneeded multitable_view assignment
sql_view.cc:
  fix potential memorry overrun in ref_array
  asssign multitable_view in time of view creation (BUG#12569)


sql/sql_view.cc:
  fix potential memorry overrun in ref_array
  asssign multitable_view in time of view creation
sql/table.cc:
  remove unneeded multitable_view assignment