x265: Use the encoder defaults

Reset the settings as it is done for x264.
texi2pod: Make it output a single encoding string

Intermixing =encoding utf-8 in the file can confuse some pod2man
implementations.
mpegts: Allow custom max resync size
ppc: Support little endian intreadwrite
x11grab: Fallback to normal XImage if SHM is not supported
x11grab: Refactor pixel format parsing
time: Use clock_gettime if the monotonic clock is available

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
rtpdec: HEVC/H.265 support

As specified in draft-ietf-payload-rtp-h265-06.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>