x86, realmode: Unbreak the ia64 build of drivers/acpi/sleep.c

Revert usage of acpi_wakeup_address and move definition
to x86 architecture code in order to make compilation work
in ia64.

[jsakkine: tested compilation in ia64/x86-64 and added
proper commit message]

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Originally-by: H. Peter Anvin <hpa@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1338370421-27735-1-git-send-email-jarkko.sakkinen@intel.com
Cc: Tony Luck <tony.luck@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 724aa44..0c44630 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -29,6 +29,7 @@
 #include <asm/processor.h>
 #include <asm/mmu.h>
 #include <asm/mpspec.h>
+#include <asm/realmode.h>
 
 #define COMPILER_DEPENDENT_INT64   long long
 #define COMPILER_DEPENDENT_UINT64  unsigned long long
@@ -116,10 +117,8 @@
 /* Low-level suspend routine. */
 extern int acpi_suspend_lowlevel(void);
 
-extern const unsigned char acpi_wakeup_code[];
-
-/* early initialization routine */
-extern void acpi_reserve_wakeup_memory(void);
+/* Physical address to resume after wakeup */
+#define acpi_wakeup_address ((unsigned long)(real_mode_header->wakeup_start))
 
 /*
  * Check if the CPU can handle C2 and deeper
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index ebaa045..74ee4ab 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -25,8 +25,6 @@
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
 
-#include <asm/realmode.h>
-
 #include "internal.h"
 #include "sleep.h"
 
@@ -93,13 +91,11 @@
 static int acpi_sleep_prepare(u32 acpi_state)
 {
 #ifdef CONFIG_ACPI_SLEEP
-	unsigned long wakeup_pa = real_mode_header->wakeup_start;
 	/* do we have a wakeup address for S2 and S3? */
 	if (acpi_state == ACPI_STATE_S3) {
-		if (!wakeup_pa)
+		if (!acpi_wakeup_address)
 			return -EFAULT;
-		acpi_set_firmware_waking_vector(
-				(acpi_physical_address)wakeup_pa);
+		acpi_set_firmware_waking_vector(acpi_wakeup_address);
 
 	}
 	ACPI_FLUSH_CPU_CACHE();