Add a per GstAmcCodecType color_format_mapping_table

gstamc.c uses a global color_format_mapping_table to map between
color_format and video_format. In case of multi-color_formats are
mapped to one video_format, then map that video_format back will
not give the original color_format, which causes
gst_amc_codec_configure failed with something like
'does not support color format N'.

This patch implements a per GstAmcCodecType color_format_mapping_table,
which will be filled in scan_codecs stage.

This also helps to move fixups for incorrect-reported color-format to
codec_type_init_color_format_mapping_table().