Remove unnecessary gl ifdef

I'm not sure why this was originally added.
I couldn't think of a reason why the Pi would want things done differently here,
so I tried without the ifdef. I can't see any difference in behaviour,
so I think we're better off removing it.
dvdplayer: move CanSeek/CanPause to seekable interface
dvdplayer: disable seeking and pause for udp/rtp and seek for tcp
dvdplayer: move navigator state into IMenus
Re-get details from nfo file after advancing to first episodedetails
Fix color index overflow by reuse existed color in the vector. Fix #14293
[OSX] Fix always on top after restore from fullscreen.
Fix undefined reference caused by wrong detection of gcc builtin atomic functions.
avoid detect folder.jpg under 'add' item.
Check exists before listing dir, to avoid produce error log, fix #14210
fixed: when doing a format conversion from float to 32 bit int, multiply with INT32_MAX - 127, since this is the maximum value that can be stored in 32 bit float and int, if INT32_MAX gets converted to float, it gets rounded to INT32_MAX + 1 which can cause wrap around distortion
Read CD audio USB drive bug fixed

libcdio seems to allow read no more than about 10 audio sectors at once when CD audio device is connected via USB.
This patch makes XBMC read small number of sectors if default one fails. It uses more CPU but allows to use USB CD devices.
Tested on GNU/Linux x86 and RPi. (On Rpi OMXPlayer does not play CD, but I can rip tracks).
backport some constructor initializations from 92e8bc4a4361d730abac9ad3080cd6923e9d551a
Fixed: do not send Range request header when encounter error.
CGUISliderControl: only switch between selectors on <Enter> if there are more than one
Fix color tag didn't hide bug introduced by PR2725.
Linux: fix handling of zombie processes
pvr: fix channel switch for addons using other stream
- bump libnfs to 1.6
- bump libnfs to 1.6