x86: Fix symbol annotation for arch/x86/lib/clear_page_64.S::clear_page_c

Noticed the zero-sized function symbol while looking at 'perf' profiles,
it causes the profiler to display those addresses in hexa.

Turns out that this was wrong/bogus for an eternity.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Alexander van Heukelum <heukelum@fastmail.fm>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <1246366820.6538.1.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/lib/clear_page_64.S

@@ -5,15 +5,14 @@
  * Zero a page. 	
  * rdi	page
  */			
-	ALIGN
-clear_page_c:
+ENTRY(clear_page_c)
 	CFI_STARTPROC
 	movl $4096/8,%ecx
 	xorl %eax,%eax
 	rep stosq
 	ret
 	CFI_ENDPROC
-ENDPROC(clear_page)
+ENDPROC(clear_page_c)
 
 ENTRY(clear_page)
 	CFI_STARTPROC