SDL: Fix issue with vulkan-to-opengl fallback

SDL/SDLMain.cpp

@@ -615,16 +615,13 @@ int main(int argc, char *argv[]) {
 	GraphicsContext *graphicsContext = nullptr;
 	SDL_Window *window = nullptr;
 
-	bool useEmuThread;
-
 	std::string error_message;
 	if (g_Config.iGPUBackend == (int)GPUBackend::OPENGL) {
 		SDLGLGraphicsContext *ctx = new SDLGLGraphicsContext();
 		if (ctx->Init(window, x, y, mode, &error_message) != 0) {
 			printf("GL init error '%s'\n", error_message.c_str());
 		}
 		graphicsContext = ctx;
-		useEmuThread = true;
 	} else if (g_Config.iGPUBackend == (int)GPUBackend::VULKAN) {
 		SDLVulkanGraphicsContext *ctx = new SDLVulkanGraphicsContext();
 		if (!ctx->Init(window, x, y, mode, &error_message)) {
@@ -638,9 +635,10 @@ int main(int argc, char *argv[]) {
 		} else {
 			graphicsContext = ctx;
 		}
-		useEmuThread = false;
 	}
 
+	bool useEmuThread = g_Config.iGPUBackend == (int)GPUBackend::OPENGL;
+
 	SDL_SetWindowTitle(window, (app_name_nice + " " + PPSSPP_GIT_VERSION).c_str());
 
 	// Since we render from the main thread, there's nothing done here, but we call it to avoid confusion.