Those values are decoder-independent and are also use by the VA-API
encoder.

This is more consistent with the rest of libav and frees up the hevc.h
name for decoder-independent shared declarations.

Factor out the parameter sets into a separate struct and use it instead.

This will allow us to reuse this code in the parser.

hevc seems to be the only place where the C implementation
of the av_clip function is explicitly selected, precluding
platform-specific optimizations
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Prevents shifts with undefined behavior, as no syntax element has a valid
value greater than 1 << 31.

Bug-Id: CID 1206635

Only its size is actually used. Silence a clang warning.

Initially written by Guillaume Martres <smarter@ubuntu.com> as a GSoC
project. Further contributions by the OpenHEVC project and other
developers, namely:

Mickaël Raulet <mraulet@insa-rennes.fr>
Seppo Tomperi <seppo.tomperi@vtt.fi>
Gildas Cocherel <gildas.cocherel@laposte.net>
Khaled Jerbi <khaled_jerbi@yahoo.fr>
Wassim Hamidouche <wassim.hamidouche@insa-rennes.fr>
Vittorio Giovara <vittorio.giovara@gmail.com>
Jan Ekström <jeebjp@gmail.com>
Anton Khirnov <anton@khirnov.net>
Martin Storsjö <martin@martin.st>
Luca Barbato <lu_zero@gentoo.org>
Yusuke Nakamura <muken.the.vfrmaniac@gmail.com>
Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Diego Biurrun <diego@biurrun.de>
Signed-off-by: Anton Khirnov <anton@khirnov.net>