src: Add vk_format_utils.h to UtilityHeaders

The library originates from Vulkan-ValidationLayers, but is being moved
into this repo to make it easier for others to use it.

The library has also been modified to be header only and C compatible,
which allows more developers to be able to use it. This does require some
changes, but only affects the vkuFormatElementSize and vkuFormatTexelSize
functions which used default parameters. Two new functions,
vkuFormatElementSizeWithAspect and vkuFormatTexelSizeWithAspect have been
added to handle the non-default image aspect case (the default was COLOR_BIT).

Renaming was done using the following convention:
* public header files begin with `vk_`
* enums begin with VKU_FORMAT_
* functions begin with vku

scripts/generate_source.py

@@ -24,6 +24,7 @@ def RunGenerators(api: str, registry: str, targetFilter: str) -> None:
     from generators.base_generator import BaseGeneratorOptions
     from generators.dispatch_table_generator import DispatchTableOutputGenerator
     from generators.enum_string_helper_generator import EnumStringHelperOutputGenerator
+    from generators.format_utils_generator import FormatUtilsOutputGenerator
 
     # Build up a list of all generators and custom options
     generators = {
@@ -35,6 +36,10 @@ def RunGenerators(api: str, registry: str, targetFilter: str) -> None:
             'generator' : EnumStringHelperOutputGenerator,
             'directory' : 'include/vulkan',
         },
+        'vk_format_utils.h' : {
+            'generator' : FormatUtilsOutputGenerator,
+            'directory' : 'include/vulkan/utility',
+        },
     }
 
     if (targetFilter and targetFilter not in generators.keys()):