replace remaining PIX_FMT_* flags with AV_PIX_FMT_FLAG_*

libavcodec/dpxenc.c

libavcodec/imgconvert.c

libavcodec/utils.c

libavdevice/lavfi.c

libavfilter/drawutils.c

libavfilter/formats.c

libavfilter/vf_extractplanes.c

libavfilter/vf_fade.c

libavfilter/vf_hflip.c

libavfilter/vf_il.c

libavfilter/vf_kerndeint.c

libavfilter/vf_noise.c

libavfilter/vf_swapuv.c

libavfilter/vf_telecine.c

libavfilter/vf_transpose.c

libavformat/img2enc.c

libavutil/imgutils.c

libavutil/pixdesc.c

libswscale/output.c

libswscale/swscale.c