SDL-1.2: atari: fix compilation with --enable-threads

From 9542643a8ec991fab35b02c589a7466eba635f6a Mon Sep 17 00:00:00 2001
From: Medour Mehdi <[EMAIL REDACTED]>
Date: Fri, 8 Dec 2023 23:19:56 +0100
Subject: [PATCH] atari: fix compilation with --enable-threads

Thread support implies SDL_TIMER_UNIX while SDL_AtariMint_CheckTimer() is available only with SDL_TIMER_MINT so it must not be used.
---
 src/video/ataricommon/SDL_atarievents.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/video/ataricommon/SDL_atarievents.c b/src/video/ataricommon/SDL_atarievents.c
index c4dc0f38..f4c4ad28 100644
--- a/src/video/ataricommon/SDL_atarievents.c
+++ b/src/video/ataricommon/SDL_atarievents.c
@@ -45,7 +45,9 @@
 /* from src/audio/mint/SDL_mintaudio.c */
 void SDL_AtariMint_UpdateAudio(void);
 /* from src/timer/mint/SDL_systimer.c */
+#ifdef SDL_TIMER_MINT
 void SDL_AtariMint_CheckTimer(void);
+#endif
 
 enum {
 	MCH_ST=0,
@@ -261,5 +263,9 @@ SDL_keysym *SDL_Atari_TranslateKey(int scancode, SDL_keysym *keysym,
 void SDL_AtariMint_BackgroundTasks(void)
 {
 	SDL_AtariMint_UpdateAudio();
+#ifdef SDL_TIMER_MINT
 	if (SDL_timer_running) SDL_AtariMint_CheckTimer();
+#else
+	if (SDL_timer_running) SDL_ThreadedTimerCheck();
+#endif
 }