drivers: power: ltp8800: Add LTP8800 driver

[cencarna]

Add LTP8800 driver

The LTP8800 is a family of step-down μModule regulators that provides microprocessor core voltage from 54V power distribution architecture. LTP8800 features remote configurability and telemetry monitoring of power management parameters over PMBus—an open standard I2C-based digital interface protocol.

PR Type

• [ ] Bug fix (change that fixes an issue)
• [x] New feature (change that adds new functionality)
• [ ] Breaking change (has dependencies in other repos or will cause CI to fail)

PR Checklist

• [x] I have followed the Coding style guidelines
• [x] I have performed a self-review of the changes
• [x] I have commented my code, at least hard-to-understand parts
• [x] I have build all projects affected by the changes in this PR
• [x] I have tested in hardware affected projects, at the relevant boards
• [x] I have signed off all commits from this PR
• [x] I have updated the documentation (wiki pages, ReadMe etc), if applies

[buha]

i think it looks good overall, just please address the comments above and do a rebase to fix the conflicts

[cencarna]

v2:

• Parenthesized C macros
• Updated license