acpi: Remove header dependency

In order to avoid future header hell, remove the inclusion of
proc_fs.h from acpi_bus.h. All it needs is a forward declaration of a
struct.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lkml.kernel.org/r/20200321113241.246190285@linutronix.de

drivers/platform/x86/dell-smo8800.c

@@ -16,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/miscdevice.h>
 #include <linux/uaccess.h>
+#include <linux/fs.h>
 
 struct smo8800_device {
 	u32 irq;                     /* acpi device irq */

drivers/platform/x86/wmi.c

@@ -29,6 +29,7 @@
 #include <linux/uaccess.h>
 #include <linux/uuid.h>
 #include <linux/wmi.h>
+#include <linux/fs.h>
 #include <uapi/linux/wmi.h>
 
 ACPI_MODULE_NAME("wmi");

drivers/thermal/intel/int340x_thermal/acpi_thermal_rel.c

@@ -19,6 +19,7 @@
 #include <linux/acpi.h>
 #include <linux/uaccess.h>
 #include <linux/miscdevice.h>
+#include <linux/fs.h>
 #include "acpi_thermal_rel.h"
 
 static acpi_handle acpi_thermal_rel_handle;

include/acpi/acpi_bus.h

@@ -80,7 +80,7 @@ bool acpi_dev_present(const char *hid, const char *uid, s64 hrv);
 
 #ifdef CONFIG_ACPI
 
-#include <linux/proc_fs.h>
+struct proc_dir_entry;
 
 #define ACPI_BUS_FILE_ROOT	"acpi"
 extern struct proc_dir_entry *acpi_root_dir;