pinctrl: intel: fix build warnings about export.h

After commit a934a57 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") and 7d95680 ("scripts/misc-check:
check unnecessary #include <linux/export.h> when W=1"), we get some build
warnings with W=1:

pinctrl-intel.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing

So fix these build warnings for the driver code.

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Author: andy-shev

drivers/pinctrl/intel/pinctrl-intel.c

@@ -9,6 +9,7 @@
 
 #include <linux/acpi.h>
 #include <linux/cleanup.h>
+#include <linux/export.h>
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/log2.h>