MAINTAINERS: Add reference to pn544.h platform data header

The platform data header for PN544 based NFC devices should
also be mentioned here.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

MAINTAINERS

@@ -5067,6 +5067,7 @@ F:	net/nfc/
 F:	include/linux/nfc.h
 F:	include/net/nfc/
 F:	drivers/nfc/
+F:	include/linux/platform_data/pn544.h
 
 NFS, SUNRPC, AND LOCKD CLIENTS
 M:	Trond Myklebust <Trond.Myklebust@netapp.com>