[3.10] gh-93738: Documentation C syntax (:c:type:<C type> -> :c:expr:<C type>) (GH-97768) (#97925)

:c:type:`<C type>` -> :c:expr:`<C type>`

Co-authored-by: Łukasz Langa <lukasz@langa.pl>
(cherry picked from commit 0031e62973801d34a9e19ab7bb199e9668e32d7b)

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>