intel_idle: clean up the (new) state_update_enter_method function

JIRA: https://issues.redhat.com/browse/RHEL-11351



commit 7826c069
Author: Arjan van de Ven <arjan@linux.intel.com>
Date:   Mon Jun 5 15:47:14 2023 +0000

    intel_idle: clean up the (new) state_update_enter_method function

    Now that the logic for state_update_enter_method() is in its own
    function, the long if .. else if .. else if .. else if chain
    can be simplified by just returning from the function
    at the various places. This does not change functionality,
    but it makes the logic much simpler to read or modify later.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: David Arcari <darcari@redhat.com>