mfd: add ezx_pcap_setbits

Provides an atomic set_bits functions, as needed by the pcap-regulator
driver.

Signed-off-by: Daniel Ribeiro <drwyrm@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/ezx-pcap.h b/include/linux/mfd/ezx-pcap.h
index b15caac..dec82b0b0 100644
--- a/include/linux/mfd/ezx-pcap.h
+++ b/include/linux/mfd/ezx-pcap.h
@@ -25,6 +25,7 @@
 
 int ezx_pcap_write(struct pcap_chip *, u8, u32);
 int ezx_pcap_read(struct pcap_chip *, u8, u32 *);
+int ezx_pcap_set_bits(struct pcap_chip *, u8, u32, u32);
 int pcap_to_irq(struct pcap_chip *, int);
 int irq_to_pcap(struct pcap_chip *, int);
 int pcap_adc_async(struct pcap_chip *, u8, u32, u8[], void *, void *);