Cherry pick documentation for ROCm 6.3

[bstefanuk]

This PR cherry picks the following commits into the docs/6.3 branch:

• 09ec347
• 7ac8e75
• 9b35483

[SwRaw]

@bstefanuk Can we add the content from Introduction into index.rst? The introduction file shouldn't be required as a separate entity.

[bstefanuk]

@SwRaw I like having a document to introduce the concepts in Tensile, so I would prefer to keep it. We can add more content to it to make it a more meaningful standalone document, if it makes sense.

[SwRaw]

@SwRaw I like having a document to introduce the concepts in Tensile, so I would prefer to keep it. We can add more content to it to make it a more meaningful standalone document, if it makes sense.

@bstefanuk I have added the content from introduction into index.rst and prefer to remove introduction file. Once we have enough content , we can plan something for later. Right now, its better to include the introduction on the index page.

[bstefanuk]

Comments on this branch are captured in #2056 and include largely changes of taste. Moving forward with merge for 6.3 docs.