drivers: intel: ssp: Fix checked expression in WAIT_FOR()

The function dai_ssp_poll_for_register_delay() is meant to poll the
register until the value of the mask bits is equal to the "val"
argument or until poll timeout has occured. WAIT_FOR() returns the value
of the checked expression, so the check should be modified accordingly.
This should prevent the errors seen during every SSP trigger as below:

<err> dai_intel_ssp: dai_ssp_poll_for_register_delay poll timeout reg 487432 mask 4 val 4 us 125
<err> dai_intel_ssp: dai_ssp_poll_for_register_delay poll timeout reg 487496 mask 63 val 0 us 937

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>