Add an AV_PIX_FMT_NE macro for RGB32FBE/RGB32FLE and also one for
RGBA32FBE/RGBA32FLE for packed 32-bit float RGB samples, and also
packed 32-bit float RGBA samples, respectively.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Leo Izen <leo.izen@gmail.com>