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>
diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 082e881..248642f 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/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>
diff --git a/drivers/sfi/sfi_acpi.c b/drivers/sfi/sfi_acpi.c
index 5e753d7..d277b36 100644
--- a/drivers/sfi/sfi_acpi.c
+++ b/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"
 
 /*
diff --git a/include/linux/sfi_acpi.h b/include/linux/sfi_acpi.h
index 2cfcb79..4723bbf 100644
--- a/include/linux/sfi_acpi.h
+++ b/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 */