Fix rotary positional embedding dimension mismatch in Wan and SkyReels V2 transformers (#12594)
* Fix rotary positional embedding dimension mismatch in Wan and SkyReels V2 transformers
- Store t_dim, h_dim, w_dim as instance variables in WanRotaryPosEmbed and SkyReelsV2RotaryPosEmbed __init__
- Use stored dimensions in forward() instead of recalculating with different formula
- Fixes inconsistency between init (using // 6) and forward (using // 3)
- Ensures split_sizes matches the dimensions used to create rotary embeddings
* quality fix
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Co-authored-by: Charchit Sharma <charchitsharma@A-267.local>