rtmphttp: Check for both 0 and AVERROR_EOF

This makes RTMPT work again - it was broken by 5d876be87a.

Signed-off-by: Martin Storsjö <martin@martin.st>
lavc: use buf[0] instead of data[0] in checks whether a frame is allocated

data[0] may be NULL for valid frames with hwaccel pixel formats.
dcadec: simplify an expression

Signed-off-by: Diego Biurrun <diego@biurrun.de>
aac_ac3_parser: simplify an expression

Signed-off-by: Diego Biurrun <diego@biurrun.de>
mpegvideo: Fix swapping of UV planes for VCR2
configure: Don't use symlinks for creating the out of tree makefile

On some platforms (such as msys), symlinks are (poorly) emulated
by simply creating a copy of the file.

This means that when building out of tree, the build tree gets
a copy of the original makefile, which can lead to unintuitive
build errors when the original makefile gets updated later.

Instead simply create a stub makefile which includes the real
one.

Signed-off-by: Martin Storsjö <martin@martin.st>