`h0oni/deskpad` and `hotduck`: adjust layout names

[fauxpark]

Description

⚠ h0oni/deskpad: "LAYOUT_all" should be "LAYOUT" unless additional layouts are provided.
⚠ h0oni/hotduck: "LAYOUT_all" should be "LAYOUT" unless additional layouts are provided.

deskpad is a very simple 1x5 + encoder. hotduck uses all matrix positions and by looking at the physical layout it seems reasonable to assume there are no other possible configurations.

Types of Changes

• [ ] Core
• [ ] Bugfix
• [ ] New feature
• [x] Enhancement/optimization
• [x] Keyboard (addition or update)
• [x] Keymap/layout/userspace (addition or update)
• [ ] Documentation

Issues Fixed or Closed by This PR

Checklist

• [x] My code follows the code style of this project: C, Python
• [x] I have read the PR Checklist document and have made the appropriate changes.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] I have tested the changes and verified that they work and don't break anything (as well as I can manage).