iidx: allow main window to receive touches in windows TDJ subscreen mode (#850)

## Link to GitHub Issue or related Pull Request, if one exists
n/a

## Description of change
This allows API touches to be recognized even if the main window is in
focus.

## Testing

src/spice2x/rawinput/rawinput.cpp

@@ -660,7 +660,8 @@ void rawinput::RawInputManager::devices_scan_rawinput(RAWINPUTDEVICELIST *device
                     if (logical_max > field_max) {
                         log_info(
                             "rawinput",
-                            "value cap {} LogicalMax exceeds bit width, fixing it up: {} -> {}",
+                            "device {}: value cap {} LogicalMax exceeds bit width, fixing it up: {} -> {}",
+                            new_device.name,
                             value_cap_num,
                             value_caps.LogicalMax,
                             field_max

src/spice2x/touch/native/inject.cpp

@@ -394,11 +394,10 @@ namespace nativetouch::inject {
     // preserve native registration and attach mouse injection to the touch window
     static BOOL WINAPI RegisterTouchWindowHook(HWND window, ULONG flags) {
 
-        // for TDJ in windowed subscreen mode, the main game window is
-        // target for delivering touch messages, not the subscreen
+        // TDJ handles touches on the main window, including contacts that the
+        // dedicated subscreen forwards there
         if (GRAPHICS_IIDX_WSUB && window != TDJ_SUBSCREEN_WINDOW) {
             touch_delivery_window.store(window, std::memory_order_release);
-            return TRUE;
         }
 
         // call original