Phaser: Make set_nco_phase set the phase of the NCO

Previous to this commit `set_nco_phase()` set the phase of the DUC instead
of the NCO. Setting the phase of the NCO may be desirable to utilise the
auto-sync functionality of the double-buffered DAC-NCO settings.

Signed-off-by: Marius Weber <marius.weber@physics.ox.ac.uk>

artiq/coredevice/phaser.py

@@ -889,7 +889,7 @@ class PhaserChannel:
         :param phase: NCO phase in turns
         """
         pow = int32(round(phase*(1 << 16)))
-        self.set_duc_phase_mu(pow)
+        self.set_nco_phase_mu(pow)
 
     @kernel
     def set_att_mu(self, data):