docs: use inline-code instead of default role

A single backtick escaped string in Sphinx refers to the "default role"
which is vague, and in practice ends up producing the HTML cite-element.
That's almost certainly not what these uses wanted.

A bunch of these would probably be better served using appropriate roles
instead of inline-code markup, but this is almost certainly what was
meant here instead. Let's not let perfect be the enemy of good here, and
just do what was intended. Using the right roles everywhere is a big
task.

I usually don't do changes like these to the relnotes, but in this case
there were a *single* article that had these mistakes. I assume that was
an early bug in the script that generateg the relnotes. Let's patch it,
so we don't get misrendering if we change the default-role.

Reviewed-by: Yonggang Luo <luoyonggang@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19494>

docs/vulkan/base-objs.rst

@@ -26,7 +26,7 @@ The root base struct for all Vulkan objects is
 the Vulkan API *must* inherit from :cpp:struct:`vk_object_base` by having a
 :cpp:struct:`vk_object_base` or some struct that inherits from
 :cpp:struct:`vk_object_base` as the driver struct's first member.  Even
-though we have `container_of()` and use it liberally, the
+though we have ``container_of()`` and use it liberally, the
 :cpp:struct:`vk_object_base` should be the first member as there are a few
 places, particularly in the logging framework, where we use void pointers
 to avoid casting and this only works if the address of the driver struct is