SDL: fix SDL_FindFreePlayerIndex so it can really return -1. (a7096)

SDL Commits
#1 
From a70964aaf4e70a223a8dc5407ba06f62b80a704f Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Wed, 8 Mar 2023 20:00:50 +0300
Subject: [PATCH] fix SDL_FindFreePlayerIndex so it can really return -1.

---
 src/joystick/SDL_joystick.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/joystick/SDL_joystick.c b/src/joystick/SDL_joystick.c
index 0a74be113612..c3120e724559 100644
--- a/src/joystick/SDL_joystick.c
+++ b/src/joystick/SDL_joystick.c
@@ -202,7 +202,7 @@ static SDL_bool SDL_GetDriverAndJoystickIndex(int device_index, SDL_JoystickDriv
 
 static int SDL_FindFreePlayerIndex()
 {
-    int player_index = -1;
+    int player_index;
 
     SDL_AssertJoysticksLocked();
 
@@ -211,7 +211,7 @@ static int SDL_FindFreePlayerIndex()
             return player_index;
         }
     }
-    return player_index;
+    return -1;
 }
 
 static int SDL_GetPlayerIndexForJoystickID(SDL_JoystickID instance_id)