Revert "eventpoll: fix sphinx documentation build warning"

This reverts commit ecb6cc0f.

Upstream commit f2e467a4 ("eventpoll: Fix semi-unbounded recursion")
caused a regression in LTP test epoll_ctl04. In order to temporarily
revert such commit cleanly this commit also needs to be reverted. It can
be reapplied once the fix is determined.

Bug: 435559836
Link: https://lore.kernel.org/all/aIvusYlauznxttGc@google.com/


Change-Id: I3aee0d69aebc8e86f6e29766c4441135d8a00755
Signed-off-by: Carlos Llamas <cmllamas@google.com>