namespace sts -> namespace ams

namespace sts::ams -> ams::exosphere, ams::.

This is to facilitate future use of ams:: namespace code in
mesosphere, as we'll want to include ams::util, ams::result, ams::svc...

stratosphere/libstratosphere/source/dd/dd_io_mappings.cpp

@@ -15,7 +15,7 @@
  */
 #include <stratosphere.hpp>
 
-namespace sts::dd {
+namespace ams::dd {
 
     uintptr_t QueryIoMapping(uintptr_t phys_addr, size_t size) {
         u64 virtual_addr;