ltcf-c.sh: clear ac_cv_prog_cc_pic for DJGPP.

* ltcf-c.sh: clear ac_cv_prog_cc_pic for DJGPP. Do not add
'-DPIC' to ac_cv_prog_cc_pic for DJGPP.
* ltcf-cxx.sh: likewise.
* ltcf-gcj.sh: likewise.
* ltconfig.sh: fix typo.

From-SVN: r38624