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/lguest/boot.c b/arch/x86/lguest/boot.c
index c751e3c..aa0bdd5 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -229,7 +229,7 @@
 /* Changing to a different IDT is very rare: we keep the IDT up-to-date every
  * time it is written, so we can simply loop through all entries and tell the
  * Host about them. */
-static void lguest_load_idt(const struct Xgt_desc_struct *desc)
+static void lguest_load_idt(const struct desc_ptr *desc)
 {
 	unsigned int i;
 	struct desc_struct *idt = (void *)desc->address;
@@ -252,7 +252,7 @@
  * hypercall and use that repeatedly to load a new IDT.  I don't think it
  * really matters, but wouldn't it be nice if they were the same?
  */
-static void lguest_load_gdt(const struct Xgt_desc_struct *desc)
+static void lguest_load_gdt(const struct desc_ptr *desc)
 {
 	BUG_ON((desc->size+1)/8 != GDT_ENTRIES);
 	hcall(LHCALL_LOAD_GDT, __pa(desc->address), GDT_ENTRIES, 0);