Fix the S10 arch file comments for routing segments and switches

[kimiatkh]

Description

This PR addresses the outdated comments for the routing architecture model of the S10 architecture file. The comments were based on an old version of VPR where different x and y wire segments could not be modeled. The comments have been updated to reflect the new routing model that captures horizontal and vertical routing wires separately.

Types of changes

• [ x] Bug fix (change which fixes an issue)
• [ ] New feature (change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

[vaughnbetz]

Thanks @kimiatkh !