Originally this was caused by rBc71a8e837616: UI: Fix incorrect RNA percentage property definitions.
Above commit wasnt renaming RNA definitions, but not the occurances were
RNA values were set.
In 3.0, we had improvements to pose-sliding tools (D9054) where this was
somewhat ironed out (only partially, see D12187).
But since the pose-sliding improvements are not part of 2.93, we have to
correct this in 2.93 ONLY.