Update system optimization guides headings (#3422)

* update headings to system optimization

* update index

* conv tuning-guides.md to rst

* shorten system optimization landing page

* update conf.py

update toc order

add space

* Update docs/how-to/tuning-guides.rst

Co-authored-by: Leo Paoletti <164940351+lpaoletti@users.noreply.github.com>

* update keywords

* update intro

---------

Co-authored-by: Leo Paoletti <164940351+lpaoletti@users.noreply.github.com>

docs/sphinx/_toc.yml.in

@@ -81,16 +81,17 @@ subtrees:
       - file: how-to/llm-fine-tuning-optimization/optimizing-triton-kernel.rst
         title: Optimizing Triton kernels
       - file: how-to/llm-fine-tuning-optimization/profiling-and-debugging.rst
-  - file: how-to/tuning-guides.md
+  - file: how-to/tuning-guides.rst
     title: System optimization
     subtrees:
     - entries:
-      - file: how-to/tuning-guides/mi100.md
-        title: MI100
       - file: how-to/tuning-guides/mi200.md
-        title: MI200
+        title: AMD Instinct MI200
+      - file: how-to/tuning-guides/mi100.md
+        title: AMD Instinct MI100
       - file: how-to/tuning-guides/w6000-v620.md
-        title: RDNA2
+        title: AMD RDNA 2
+  - file: how-to/system-debugging.md
   - file: how-to/gpu-enabled-mpi.rst
     title: Using MPI
   - file: conceptual/compiler-topics.md
@@ -105,8 +106,6 @@ subtrees:
         title: OpenMP support
   - file: how-to/setting-cus
     title: Setting the number of CUs  
-  - file: how-to/system-debugging.md
-    title: Debugging
   - url: https://github.com/amd/rocm-examples
     title: GitHub examples