Use cl-lib functions/macros instead of cl.el ones

[syohex]

This fixes some byte-compile warnings as below.

In end of data:
dtk.el:1597:1:Warning: the following functions are not known to be defined: case, :osis,
    :plain, second, map, destructuring-bind, strongs-number, w,
    divineName, transChange, q, div, equalp, chapter, verse, l, lg,
    note, milestone, lb, t, multiple-value-bind, last-line-parsed-n,
    do, nil, concatenate, return, incf, values, subseq, defstruct,
    rest, dtk-dict-entry-word, dtk-dict-entry-def,
    dtk-dict-entry-crossrefs, (setf dtk-dict-entry-key), first,
    make-dtk-dict-entry