MAINTAINERS: Add INTEL MERRIFIELD GPIO entry

Add gpio-merrifield.c to MAINTAINERS database per Linus' ask.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

MAINTAINERS

@@ -6004,6 +6004,12 @@ L:     linux-rdma@vger.kernel.org
 S:     Supported
 F:     drivers/infiniband/hw/i40iw/
 
+INTEL MERRIFIELD GPIO DRIVER
+M:	Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+L:	linux-gpio@vger.kernel.org
+S:	Maintained
+F:	drivers/gpio/gpio-merrifield.c
+
 INTEL-MID GPIO DRIVER
 M:	David Cohen <david.a.cohen@linux.intel.com>
 L:	linux-gpio@vger.kernel.org