GKI: export dev_pm_qos_read_value

min_freq and max_freq from sysfs now go to the dev_pm_qos_request
interface, so porting will require access to dev_pm_qos_read_value.

Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Fixes: 27dbc542 ("PM / devfreq: Use PM QoS for sysfs min/max_freq")
Bug: 165523817
Change-Id: I6837f8d75a61faf8bf18d1b9a37419632e5c7134
(cherry picked from commit dc32196ca1bf69f0040e0a8732179dd9cc3d8f30)
Signed-off-by: Will McVicker <willmcvicker@google.com>