* docs: clean up SLES tab-sets
- Always use a tab-set for SLES 15.4
- In the toplevel SLES title don't say version 15
- harmonize the `:sync:` labels between documents
* docs: Misc fixes in installation
- Fix rocm repository url in the installer script installation for SLES
- Add a missing :sync: tab in installation prerequisites
* docs: add SLES 15.5 support to installation and OS support pages