configure: Check for support for labels in the inline assembly

Use this for enabling the ppc timer.h implementation only on
assemblers that support labels in the inline assembly.

Signed-off-by: Martin Storsjö <martin@martin.st>
pcx: K&R formatting cosmetics
pcx: Do not overread source buffer in pcx_rle_decode

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
mlpdsp: x86: Respect cpuflags
mlpdec: Do not set invalid context in read_restart_header

The faulty values rippled further down the codepath causing a
hard-to-track segfault in the assembly code.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
vdpau: use the correct namespace for the union

Vdp is used by libvdpau, use AVVDPAU as used for the rest.

Reported-by: Alexis Ballier <aballier@gentoo.org>
pcm: always use codec->id instead of codec_id

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
dca: Error out on missing DSYNC

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
dca: Respect the current limits in the downmixing capabilities

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
fate: use current syntax for the scale filter

Signed-off-by: Martin Storsjö <martin@martin.st>
Merge commit 'ef5b70affc6376bfeadd1ff649b79bad9a124fa8'

* commit 'ef5b70affc6376bfeadd1ff649b79bad9a124fa8':
  configure: Check for support for labels in the inline assembly

The timer code is not placed under ifdef as ours does not use labels

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '170fb593c617cd797d00cf05bfb8d8c21d612893'

* commit '170fb593c617cd797d00cf05bfb8d8c21d612893':
  pcx: K&R formatting cosmetics

Conflicts:
	libavcodec/pcx.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '3abde1a3b49cf299f2aae4eaae6b6cb5270bdc22'

* commit '3abde1a3b49cf299f2aae4eaae6b6cb5270bdc22':
  pcx: Do not overread source buffer in pcx_rle_decode

Conflicts:
	libavcodec/pcx.c

See: 8cd1c0febe88b757e915e9af15559575c21ca728
Bytestream based system is left in place and not switched to buf+end, such switch would be
a step backward

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '2b379a925162b6783bd9a81dc03e647e8b65494c'

* commit '2b379a925162b6783bd9a81dc03e647e8b65494c':
  mlpdsp: x86: Respect cpuflags

Conflicts:
	libavcodec/x86/mlpdsp.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'e9d394f3fad7e8fd8fc80e3b33cb045bbaceb446'

* commit 'e9d394f3fad7e8fd8fc80e3b33cb045bbaceb446':
  mlpdec: Do not set invalid context in read_restart_header

Conflicts:
	libavcodec/mlpdec.c

See: a9cd12ee2afb3f3aad783c396816b23d8513f472

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'c0d973c41b4568d5bad1295879e35cfa611bdcf2'

* commit 'c0d973c41b4568d5bad1295879e35cfa611bdcf2':
  vdpau: use the correct namespace for the union

Conflicts:
	libavcodec/vdpau.h

See: 68dfe530e0fb03b4d21dfe37f8a572b95c68485e

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'c82da343e635663605bd81c59d872bee3182da73'

* commit 'c82da343e635663605bd81c59d872bee3182da73':
  pcm: always use codec->id instead of codec_id

This is not merged as we consistently use codec_id, while libav against what
the comit message might hint at mixes both in the decoder.
Its fine to use either but it should be consistent.

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'f261e508459e28beca59868a878e1519a44bb678'

* commit 'f261e508459e28beca59868a878e1519a44bb678':
  dca: Error out on missing DSYNC

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '3802833bc1f79775a1547c5e427fed6e92b77e53'

* commit '3802833bc1f79775a1547c5e427fed6e92b77e53':
  dca: Respect the current limits in the downmixing capabilities

Conflicts:
	libavcodec/dcadec.c

See: 8e77c3846e91b1af9df4084736257d9899156eef

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '52ea29867070243385220a223d7512ea7d4ae2d2'

* commit '52ea29867070243385220a223d7512ea7d4ae2d2':
  fate: use current syntax for the scale filter

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