ARM: 8907/1: arch: reuse addr variable in pfn_valid

Avoid calling __pfn_to_phys twice.
Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arch/arm/mm/init.c

@@ -180,7 +180,7 @@ int pfn_valid(unsigned long pfn)
 	if (__phys_to_pfn(addr) != pfn)
 		return 0;
 
-	return memblock_is_map_memory(__pfn_to_phys(pfn));
+	return memblock_is_map_memory(addr);
 }
 EXPORT_SYMBOL(pfn_valid);
 #endif