Correct modbus address limits

[uSlackr]

Write coil and write register allow for 16 bit addresses.
See: #66366

Breaking change

Proposed change

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• [x ] Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Modbus integration Write register invalid limit #66366
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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[probot-home-assistant]

Hey there @adamchengtkc, @janiversen, @vzahradnik, mind taking a look at this pull request as it has been labeled with an integration (modbus) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[janiversen]

LGTM.

[janiversen]

LGTM

[frenck]

Thanks, @uSlackr 👍