It was converted over ARGB32PM, when it should have been directly
converted to not lose accuracy, instead there was an unnecessary direct
ARGB32->RGB30 conversion, which was converted to the necessary type.
This also improves the selection of conversion over ARGB32PM or RGBA64PM
for ARGB32 and RGBA8888 by using 32-bit conversion when alpha is not
relevant.
Change-Id: I5990d8a23b2909d3910d8c1213fa46477742b052
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>
52a3f1b00c