iidx,sdvx: detect SuperstepSound init failures and log a message upon crash (#376)

## Link to GitHub Issue, if one exists
#345 

## Description of change
If we see SuperstepSound failure during boot, remember it, and when the
game eventually crashes, log a series of warning messages to surface why
the game likely failed to launch.

## Testing
Tested both iidx and sdvx with an audio device set to not allow
exclusive mode.

src/spice2x/games/sdvx/sdvx.cpp

@@ -24,6 +24,7 @@
 #include "io.h"
 #include "acioemu/handle.h"
 #include "cfg/configurator.h"
+#include "launcher/signal.h"
 
 static decltype(RegCloseKey) *RegCloseKey_orig = nullptr;
 static decltype(RegEnumKeyA) *RegEnumKeyA_orig = nullptr;
@@ -209,6 +210,10 @@ namespace games::sdvx {
             out = "";
             return true;
         }
+        if (data.find("SuperstepSound: Audio device is not available") != std::string::npos) {
+            launcher::signal::SUPERSTEP_SOUND_ERROR = TRUE;
+            return false;
+        }
         return false;
     }