Maya: remove invalid prefix token for non-multipart outputs

[antirotor]

Fix

This is fixing image prefixes for Vray and Redshift to not add <aov> token for outputs that are multipart (merged aovs).

Testing

Submit render to Deadline with merged AOVs from vray or redshift.

Close #3956

[ynbot]

Task linked: OP-4208 Maya + Redshift: Deadline render duplicates in output render

[LiborBatek]

Just tested it in with #3954 branch and it works normally (fixes it)....giving it just <name>.####.exr not any <AOV> tokens in the filename when using multichannel exr format.

Im just not sure if these PRs should be joined together or?

[BigRoy]

Im just not sure if these PRs should be joined together or?

They should, yes.

This one fixes what the expected output is for the renderer in the situations where multipart EXR is enabled. The other fixes what is passed to Deadline in the case multipart EXR is disabled.

[antirotor]

I've merged it together. One PR to rule them all.

[m-u-r-p-h-y]

Redshift has actually two multipart options, not very well documented and making the whole thing a true nightmare

redshiftOptions.exrForceMultilayer redshiftOptions.exrMultipart

It seems we only take into account the first one, which is the only way as with all other combinations multipart + individual aov output settings it is nearly impossible to control.