fix: handle skinning batch jobs correctly

[ekaratzas]

Purpose of change

This PR fixes the inability to batch skin or field dress multiple corpses at once. The relevant code that would check if the corpses have skin/organs only worked if a specific corpse index had been selected, i.e. if the corpse index was something other than -1.
This fixes the issue for both organs and skin as the checks are clustered together.

Fixes #4094

Describe the solution

Fix simply checks if any of the corpses have skin/organs in order to trigger the appropriate submenu selections in the butcher menu. The behavior remains effectively the same if the player is targeting a specific corpse, it only changes behavior for batch butchering.

Describe alternatives you've considered

Not fixing this in hopes of more players turning vegan.

Testing

Tested following scenarios:

• multiple corpses with skin on same tile - player can batch butcher all of them with fix
• multiple corpses, some with skin, some without on tile - batch butchering works as expected and only those with skin are butchered
• field dressing batch job with human/chicken corpses on same tile - human corpses were butchered, chickens were ignored
• butchering single corpse in a tile
• butchering single corpse out of a pile of corpses in a pile

Additional context

Butchering is messy business

Checklist

[scarf005]

was able to skin multiple corpses.