avcodec/snow_dwt: fix "incompatible pointer type" warnings

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter/vf_deshake: dont pass the wrong context into the SAD functions

This fixes pointer type warnings
The context should have been unused so this should not fix any real bug

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/jpeglsdec: add cast to silence pointer type warning

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