Revert "sched/psi: Rename existing poll members in preparation"

This reverts commit c1623d4d which is
commit 65457b74 upstream.

It is part of a patch series that breaks the Android API.  If this
series is needed in Android devices in the future, it can come back in
an ABI-safe manner.

Bug: 161946584
Change-Id: I0e49fbb45ba3881e2a6a7521cc1f44b859772ad5
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>