IA-64 has been removed from the tree, so we should also remove
the corresponding kernel-parameters documentation now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240627162458.387700-1-thuth@redhat.com