This was only used once, other checks were masking out RGN_SPLIT_PREV which isn't future proof (if other flags are added). Add RGN_ALIGN_ENUM_FROM_MASK macro, use it everywhere we need to check the alignment enum.
This was only used once, other checks were masking out RGN_SPLIT_PREV which isn't future proof (if other flags are added). Add RGN_ALIGN_ENUM_FROM_MASK macro, use it everywhere we need to check the alignment enum.