build: Conditionally build and test iirfilter
build: Conditionally build and run DCT test program
build: Conditionally compile all avcodec test programs
fate: Split audio- and video-related RealMedia targets

Signed-off-by: Diego Biurrun <diego@biurrun.de>
doc/APIchanges: mention FF_INPUT_BUFFER_PADDING_SIZE chage

Suggested-by: Andreas Cadhalpun
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'bd499d9af668aef979ec9f3f3215b8dd508c7ec1'

* commit 'bd499d9af668aef979ec9f3f3215b8dd508c7ec1':
  build: Conditionally build and test iirfilter

Conflicts:
	libavcodec/Makefile

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '16b7328058fa600d5158c84d9cc621a134eb88bc'

* commit '16b7328058fa600d5158c84d9cc621a134eb88bc':
  build: Conditionally build and run DCT test program

Conflicts:
	libavcodec/Makefile
	libavcodec/dct-test.c
	tests/fate/libavcodec.mak

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '2ce53880bfeb431decdd2fc82298c0aff823ab47'

* commit '2ce53880bfeb431decdd2fc82298c0aff823ab47':
  build: Conditionally compile all avcodec test programs

Conflicts:
	libavcodec/Makefile

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '4d2d0595cf9dd199c35aefef450952d209a56573'

* commit '4d2d0595cf9dd199c35aefef450952d209a56573':
  fate: Split audio- and video-related RealMedia targets

Conflicts:
	tests/fate/real.mak

Merged-by: Michael Niedermayer <michaelni@gmx.at>