vp8: Use 2 registers for dst_stride and src_stride in neon bilin filter

Based on a patch by Ronald S. Bultje.

Signed-off-by: Martin Storsjö <martin@martin.st>
Merge remote-tracking branch 'qatar/master'

* qatar/master:
  vp8: Use 2 registers for dst_stride and src_stride in neon bilin filter

Conflicts:
	libavcodec/arm/vp8dsp_neon.S

Merged-by: Michael Niedermayer <michaelni@gmx.at>
doc/texi2pod: make references bold

Inspired by GCC r86635.

This is more consistent with other man pages. For example in `man git`,
all the "git-help(1)" kind of cross refs are bold.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>