ACPI / DPTF: remove header search path to the parent directory

It is too much to add extra header search path for all files in
drivers/acpi/dptf/.

Fix up one C file, and remove the header search path.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/dptf/Makefile

 obj-$(CONFIG_ACPI)             += int340x_thermal.o
 obj-$(CONFIG_DPTF_POWER)	+= dptf_power.o
-
-ccflags-y += -Idrivers/acpi

drivers/acpi/dptf/int340x_thermal.c

@@ -12,7 +12,7 @@
 #include <linux/acpi.h>
 #include <linux/module.h>
 
-#include "internal.h"
+#include "../internal.h"
 
 #define INT3401_DEVICE 0X01
 static const struct acpi_device_id int340x_thermal_device_ids[] = {