[ARM] 4798/1: pcm027: fix missing header file

This patch adds a PXA2xx specific header file to control chip setup.
Without, the PCM027 BSP can't be built.

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Juergen Beisert <j.beisert@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>