x86: head_64.S cleanup - use straight move to CR4 register

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 2f59ca8..7475b4c 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -155,9 +155,7 @@
 	 */
 
 	/* Enable PAE mode and PGE */
-	xorq	%rax, %rax
-	btsq	$5, %rax
-	btsq	$7, %rax
+	movl	$(X86_CR4_PAE | X86_CR4_PGE), %eax
 	movq	%rax, %cr4
 
 	/* Setup early boot stage 4 level pagetables. */