[SWDEV-510820] Add missing goamdsmi documentation (#147)

* add API doc comments to goamdsmi.go
* update README and usage
* add sphinx directive to parse go doc
* fix walrus operator typos
* make docs more consistent
* add Go docs to index.md

---------

Signed-off-by: Arif, Maisam <Maisam.Arif@amd.com>

docs/reference/amdsmi-go-api.md

@@ -0,0 +1,33 @@
+---
+myst:
+  html_meta:
+    "description lang=en": "Explore the AMD SMI Go API."
+    "keywords": "api, smi, lib, system, management, interface, ROCm, golang"
+---
+
+# AMD SMI Go API reference
+
+The AMD SMI Go interface provides a convenient way to interact with AMD
+hardware through a simple and accessible API. The API is compatible with Go
+version 1.20 and higher and requires the AMD driver to be loaded for
+initialization. Review the [prerequisites](#go_prereqs) before getting
+started.
+
+This section provides documentation for the AMD SMI Go API. Explore these
+sections to understand the full scope of available functionalities and how to
+implement them in your applications.
+
+## GPU functions
+
+```{eval-rst}
+.. go-api-ref:: ../../goamdsmi.go
+   :section: gpu
+```
+
+## CPU functions
+
+
+```{eval-rst}
+.. go-api-ref:: ../../goamdsmi.go
+   :section: cpu
+```