x86: Fix binutils-2.21 symbol related build failures

New binutils version 2.21.0.20110302-1 started checking that the symbol
parameter to the .size directive matches the entry name's
symbol parameter, unearthing two mismatches:

  AS      arch/x86/kernel/acpi/wakeup_rm.o
  arch/x86/kernel/acpi/wakeup_rm.S: Assembler messages:
  arch/x86/kernel/acpi/wakeup_rm.S:12: Error: .size expression with symbol `wakeup_code_start' does not evaluate to a constant

  arch/x86/kernel/entry_32.S: Assembler messages:
  arch/x86/kernel/entry_32.S:1421: Error: .size expression with
  symbol `apf_page_fault' does not evaluate to a constant

The problem was discovered while using Debian's binutils
(2.21.0.20110302-1) and experimenting with binutils from
upstream.

Thanks Alexander and H.J. for the vital help.
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <1299620364-21644-1-git-send-email-sedat.dilek@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/acpi/wakeup_rm.S

@@ -9,4 +9,4 @@
 	.globl	acpi_wakeup_code
 acpi_wakeup_code:
 	.incbin	"arch/x86/kernel/acpi/realmode/wakeup.bin"
-	.size	wakeup_code_start, .-wakeup_code_start
+	.size	acpi_wakeup_code, .-acpi_wakeup_code

arch/x86/kernel/entry_32.S

@@ -1413,7 +1413,7 @@ ENTRY(async_page_fault)
 	CFI_ADJUST_CFA_OFFSET 4
 	jmp error_code
 	CFI_ENDPROC
-END(apf_page_fault)
+END(async_page_fault)
 #endif
 
 /*