feat: vulkan: add info about icd loader

Add some information about the Vulkan ICD Loader and a useful tool to
help with debugging.

Signed-off-by: Randolph Sapp <[email protected]>

Author: StaticRocket

source/linux/Foundational_Components/Graphics/Common/Vulkan.rst

@@ -15,6 +15,18 @@ intended to abstract common processing functions for developers. As a result, it
 can be written by hand but it is usually advised to use an existing abstraction
 framework, such as the previously mentioned GTK or Qt widget based framework.
 
+Like OpenCL\ |trade|, Vulkan\ |reg| has an Installable Client Driver (ICD)
+Loader to allow applications to query and pick the device it deems necessary
+instead of relying on a predefined mapping between a chosen display and backing
+vendor acceleration implementation. This means that typically an application
+that wants to use Vulkan\ |reg| should link against an ICD loader library
+instead of directly using a vendor specific library.
+
+A useful tool for debugging Vulkan\ |reg| ICD Loaders and devices is
+:command:`vulkaninfo`. This command, when run without any arguments will present
+a list of all supported devices, associated parameters, and supported
+extensions.
+
 For more information about Vulkan\ |reg| extensions see:
 
    - `<https://docs.imgtec.com/starter-guides/vulkan-hello-api-guide/html/topics/introduction.html>`_