issue: tidy up the default values in README

[pasis]

Description

Correct the default value of XLIO_UTLS_RX. Force a single convention for Enabled/Disabled .

What

Correct the default value of XLIO_UTLS_RX. Force a single convention for Enabled/Disabled .

Why ?

Tidy up the documentation.

Change type

What kind of change does this PR introduce?

• [ ] Bugfix
• [ ] Feature
• [ ] Code style update
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] CI related changes
• [x] Documentation content changes
• [ ] Tests
• [ ] Other

Check list

• [ ] Code follows the style de facto guidelines of this project
• [ ] Comments have been inserted in hard to understand places
• [ ] Documentation has been updated (if necessary)
• [ ] Test has been added (if possible)