[FFmpeg-user] Build error with libmp3lame and libshine.

[Frank Tetzel]

> The error message says...
> 
> /home/user/build/lib/libmp3lame.a(takehiro.o):(.rodata+0x0): multiple
> definition of
> `slen2_tab' /home/user/build/lib/libshine.a(tables.o):(.rodata+0xc80):
> first defined
> here /home/user/build/lib/libmp3lame.a(takehiro.o):(.rodata+0x40):
> multiple definition of
> `slen1_tab' /home/user/build/lib/libshine.a(tables.o):(.rodata+0xcc0):
> first defined here collect2: ld returned 1 exit status make: ***
> [ffmpeg_g] Error 1

These are symbol collisions between both libraries which basically means
you can't use both at the same time (with static linking). prefixes (or
namespaces in c++) are there for a good reason...

Build shared libs and link dynamically! As these functions are not part
of the API, this should work.