x86: Fix override new_cpu_data.x86 with 486

We should set X86 to 486 before use cpuid to detect the cpu type, if
we set X86 to 486 after cpuid, then we will get 486 until cpu_detect
runs.
Signed-off-by: Wang YanQing <udknight@gmail.com>
Link: http://lkml.kernel.org/r/20130628144516.GA2177@udknightAcked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/kernel/head_32.S

@@ -410,6 +410,7 @@ enable_paging:
 /*
  * Check if it is 486
  */
+	movb $4,X86			# at least 486
 	cmpl $-1,X86_CPUID
 	je is486
 
@@ -437,7 +438,6 @@ enable_paging:
 	movl %edx,X86_CAPABILITY
 
 is486:
-	movb $4,X86
 	movl $0x50022,%ecx	# set AM, WP, NE and MP
 	movl %cr0,%eax
 	andl $0x80000011,%eax	# Save PG,PE,ET