sdmmc: various fixes + logging as bugs are debugged

exosphere/mariko_fatal/source/fatal_abort_impl.cpp

@@ -19,6 +19,8 @@ namespace ams::diag {
 
     void AbortImpl() {
         AMS_SECMON_LOG("AbortImpl was called\n");
+        AMS_LOG_FLUSH();
+        reg::Write(0x4, 0xAAAAAAAA);
 
         /* TODO: Reboot */
         AMS_INFINITE_LOOP();