When changing the scan rate as part of runtime-resume process we may lose
some of the events, because:

1) for gen3 trackpads, the driver must msleep() some time to ensure that
the device is ready to accept next command;

2) for gen5 and later trackpads, the queue dumping function will simply
ignore the events when waiting for the set power mode command response.

The solution is to keep polling and report those valid events when the set
power mode command is in progress.
Signed-off-by: Dudley Du <dudl@cypress.com>
Tested-by: Jeremiah Mahler <jmmahler@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>