Fix compilation error due to missing include.

This fixes compilation error due to missing header.

 SDL_anigif.cpp: In function ‘int AG_LoadGIF_RW(SDL_RWops*, AG_Frame*, int)’:
 SDL_anigif.cpp:293:37: error: ‘malloc’ was not declared in this scope
   gd = (gifdata*)malloc( sizeof(*gd) );
                                     ^
 SDL_anigif.cpp:418:11: error: ‘free’ was not declared in this scope
   free( gd );
           ^
 make: *** [TexturePacker] Error 1
Fix compilation error related to removed structure field by ffmpeg.

ffmpeg removed reference_dts field in struct AVStream.

Related ffmpeg commit:
  http://git.videolan.org/?p=ffmpeg.git;a=commitdiff;h=2ba68dd044ca8fc591139c05563840f546a9c0c0
DVDSubtitleStream: better detect stream encoding and optimization
Use BOM detection for all supported charsets, not only UTF-8 and UTF-16LE
Do not double convert subtitle->wstring->UTF-8. Use direct conversion subtitle->UTF-8
additionally: CharsetConverter: subtitleCharsetToW -> subtitleCharsetToUtf8
[rbp/omxplayer] Cosmetic: Avoid DVDPlayer in logging message

It makes people incorrectly think DVDPlayer has been running
[spectrum] cosmetic: Use static where appropriate
[rbp] Remove PiAudio engine
[rbp] Add PiAudio sink
[spectrum] Draw spectrum as a single object

glDrawElements is called 256 times per frame, once for each bar. It is more efficient to batch up larger blocks.
This change draws the specrum with a single glDrawElements call.

Looking at visualisation in full screen mode, it used to top out at 75 fps. With this PR it can hit 125 fps.
[rbp/omxplayer] When reencoding thumbnails preserve orientation

Currently reencoded thumbnails are displayed without original orientation flag applied.
However we can write the Orientation field of IFD0 data, which means the cached thumbnail will be displayed correctly when decoded
fixed: add GIF as known header to cximage.
changed: pass detected image mimetype further down to avoid a second lookup.
imagefactory: removed unused method.
[db] changed implementation of DeleteValues()
[db] get rid of FormatSQL() and use PrepareSQL() instead
[db] fix: adds missing close dataset in CPVRDatabase
Support uClibc compilation

partly based on aports from Alpine Linux:
http://code.ohloh.net/file?fid=Up3lAbVglPtyupfNPazFHQYMKM8&cid=Sr-nRbkkE8E&s=&fp=302485&mp=&projSelected=true#L0
Merge pull request #3923 from popcornmix/cosmetic_log

[rbp/omxplayer] Cosmetic: Avoid DVDPlayer in logging message
Merge pull request #3874 from xhaggi/pvr-database

[db] improve/remove of pvr related database methods
Merge pull request #3939 from popcornmix/reenc_orient

[rbp/omxplayer] When reencoding thumbnails preserve orientation
Merge pull request #3871 from gfto/fix-compile-errors2

Fix two compilation errors.