tools/libxc: Correct comment for normalise_pagetable()

This is most likely a copy/paste mistake.

Reported-by: Bruno Alvisio <bruno.alvisio@gmail.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

tools/libxc/xc_sr_save_x86_pv.c

@@ -882,7 +882,7 @@ static int write_shared_info(struct xc_sr_context *ctx)
 }
 
 /*
- * Normalise a pagetable for the migration stream.  Performs pfn->mfn
+ * Normalise a pagetable for the migration stream.  Performs mfn->pfn
  * conversions on the ptes.
  */
 static int normalise_pagetable(struct xc_sr_context *ctx, const uint64_t *src,