x86: unify struct desc_ptr

This patch unifies struct desc_ptr between i386 and x86_64.
They can be expressed in the exact same way in C code, only
having to change the name of one of them. As Xgt_desc_struct
is ugly and big, this is the one that goes away.

There's also a padding field in i386, but it is not really
needed in the C structure definition.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 4f9e319..69507ae 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -649,7 +649,7 @@
  * it's on the real one. */
 void switch_to_new_gdt(void)
 {
-	struct Xgt_desc_struct gdt_descr;
+	struct desc_ptr gdt_descr;
 
 	gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
 	gdt_descr.size = GDT_SIZE - 1;