build: Import makedef script from c99-to-c89

This allows MSVC 2013 and ICL to build with no external
dependencies.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Merge remote-tracking branch 'qatar/master'

* qatar/master:
  build: Import makedef script from c99-to-c89

Merged-by: Michael Niedermayer <michaelni@gmx.at>
ffplay: do not call avcodec_register_all() explicitly

avcodec_register_all() is implicitly called by av_register_all().
Partially revert "Merge commit 'f187557ab4612776f7f527ecf3d40062975c3e4c'"

This partially reverts commit c0237d19a0269ff44e909434f1b2b645fad2d281
Some scripts make use of --disable-doc

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>