ams_mitm: Implement emummc Nintendo folder redirection

stratosphere/boot/source/boot_main.cpp

@@ -45,7 +45,7 @@ extern "C" {
     void __appExit(void);
 
     /* Exception handling. */
-    alignas(16) u8 __nx_exception_stack[0x1000];
+    alignas(16) u8 __nx_exception_stack[ams::os::MemoryPageSize];
     u64 __nx_exception_stack_size = sizeof(__nx_exception_stack);
     void __libnx_exception_handler(ThreadExceptionDump *ctx);
 }