sdl12-compat: fix build using c++ compilers. (b8f62)

SDL Commits
1 
From b8f62b7ca846c2274a63eb27525ffb284e2b4480 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Tue, 28 Oct 2025 20:37:00 +0300
Subject: [PATCH] fix build using c++ compilers.

---
 src/SDL12_compat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/SDL12_compat.c b/src/SDL12_compat.c
index 68051848c..3fdc4b1af 100644
--- a/src/SDL12_compat.c
+++ b/src/SDL12_compat.c
@@ -7777,7 +7777,7 @@ UpdateInputGrab(void)
     /* SDL 1.2 always grabbed input if the video mode was fullscreen. */
     if (VideoWindow20) {
         const SDL_bool isfullscreen = (VideoSurface12 && VideoSurface12->surface20 && (VideoSurface12->flags & SDL12_FULLSCREEN)) ? SDL_TRUE : SDL_FALSE;
-        const SDL_bool wantgrab = (VideoWindowGrabWanted || isfullscreen);
+        const SDL_bool wantgrab = (VideoWindowGrabWanted || isfullscreen) ? SDL_TRUE : SDL_FALSE;
         SDL20_SetWindowGrab(VideoWindow20, wantgrab);
         VideoWindowGrabbed = wantgrab;
         UpdateRelativeMouseMode();