checkpatch: allow multiple const * types

checkpatch's $Type variable does not match declarations of multiple
const * types.

This can produce false positives for things like:

  $ ./scripts/checkpatch.pl -f drivers/staging/comedi/comedidev.h
  WARNING: Missing a blank line after declarations
  #60: FILE: drivers/staging/comedi/comedidev.h:60:
  +       const struct comedi_lrange *range_table;
  +       const struct comedi_lrange *const *range_table_list;

Fix the $Type variable to support matching multiple "* const" uses.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Hartley Sweeten <HartleyS@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>