avcodec/jpeglsdec: add PAL8 support

Fixes Ticket3478

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
libavutil: Add fixed_dsp

Signed-off-by: Nedeljko Babic <nbabic@mips.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avutil/fixed_dsp: remove redundant cast

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>