SFI / ACPI: Fix warnings reported during builds with W=1

The following warnings can be seen in W=1 builds, because the original
sfi_acpi.[ch] header inclusions are incorrect:

include/linux/sfi_acpi.h:72:2: error: implicit declaration of function 'acpi_table_parse' [-Werror=implicit-function-declaration]
drivers/sfi/sfi_acpi.c:154:5: warning: no previous prototype for 'sfi_acpi_table_parse' [-Wmissing-prototypes]

Fix linux/sfi_acpi.h and modify drivers/sfi/sfi_acpi.c accordingly.
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/x86/pci/mmconfig-shared.c

@@ -12,7 +12,6 @@
 
 #include <linux/pci.h>
 #include <linux/init.h>
-#include <linux/acpi.h>
 #include <linux/sfi_acpi.h>
 #include <linux/bitmap.h>
 #include <linux/dmi.h>

drivers/sfi/sfi_acpi.c

@@ -60,9 +60,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
-#include <acpi/acpi.h>	/* FIXME: inclusion should be removed */
-
-#include <linux/sfi.h>
+#include <linux/sfi_acpi.h>
 #include "sfi_core.h"
 
 /*

include/linux/sfi_acpi.h

@@ -59,6 +59,9 @@
 #ifndef _LINUX_SFI_ACPI_H
 #define _LINUX_SFI_ACPI_H
 
+#include <linux/acpi.h>
+#include <linux/sfi.h>
+
 #ifdef CONFIG_SFI
 #include <acpi/acpi.h>	/* FIXME: inclusion should be removed */