mfd: intel-lpss: Move linux/pm.h to the local header

We now using a common macro for PM operations in Intel LPSS driver,
and, since that macro relies on the definition and macro from linux/pm.h
header file, it's logical to include it directly in intel-lpss.h.
Otherwise it's a bit fragile and requires a proper ordering
of header inclusion in C files.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/intel-lpss.h b/drivers/mfd/intel-lpss.h
index 865bbea..3a120fe 100644
--- a/drivers/mfd/intel-lpss.h
+++ b/drivers/mfd/intel-lpss.h
@@ -14,6 +14,8 @@
 #ifndef __MFD_INTEL_LPSS_H
 #define __MFD_INTEL_LPSS_H
 
+#include <linux/pm.h>
+
 struct device;
 struct resource;
 struct property_entry;