+ added a size parameter to optimize_op_const and do a sign extension of the 'a' parameter up from the specified size, so that things like (i and $ffffffff) get optimized away the same way as (i and -1)

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@26561 3ad0048d-3df7-0310-abae-a5850022a9f2