[PATCH] x86: don't open-code max_page calculation nor pfn_to_paddr()

[Jan Beulich <jbeulich@suse.com>]

As observed by Roger while reviewing a somewhat related change, there's
no need here either to open-code the (largely, i.e. once setup_max_pdx()
was called) fixed relationship between max_pdx and max_page. Further we
can avoid open-coding pfn_to_paddr() here.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1569,7 +1569,7 @@ void asmlinkage __init noreturn __start_
                 continue;
             }
             map_e = e;
-            e = (pdx_to_pfn(max_pdx - 1) + 1ULL) << PAGE_SHIFT;
+            e = pfn_to_paddr(max_page);
             printk(XENLOG_WARNING "Ignoring inaccessible memory range"
                                   " %013"PRIx64"-%013"PRIx64"\n",
                    e, map_e);