x86: unify pgd ctor/dtor

All pagetables need fundamentally the same setup and destruction, so
just use the same code for everything.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/asm-x86/pgtable_64.h b/include/asm-x86/pgtable_64.h
index 9fd87d0..a3bbf87 100644
--- a/include/asm-x86/pgtable_64.h
+++ b/include/asm-x86/pgtable_64.h
@@ -24,7 +24,7 @@
 
 #endif /* !__ASSEMBLY__ */
 
-#define SHARED_KERNEL_PMD	1
+#define SHARED_KERNEL_PMD	0
 
 /*
  * PGDIR_SHIFT determines what a top-level page table entry can map