sdl12-compat: SDL_SetVideoMode: implicit video subsys init should call Init12Video too

SDL Commits
1 
From f4fb00544a53e5f0ff2607c318668eb1787606de Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Sat, 27 Feb 2021 22:11:50 +0300
Subject: [PATCH] SDL_SetVideoMode: implicit video subsys init should call
 Init12Video too

Fixes https://github.com/libsdl-org/sdl12-compat/issues/29
---
 src/SDL12_compat.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/SDL12_compat.c b/src/SDL12_compat.c
index 8721f51..bd39a1a 100644
--- a/src/SDL12_compat.c
+++ b/src/SDL12_compat.c
@@ -2968,6 +2968,9 @@ SDL_SetVideoMode(int width, int height, int bpp, Uint32 flags12)
         if (SDL20_Init(SDL_INIT_VIDEO) < 0) {
             return NULL;
         }
+        if (Init12Video() < 0) {
+            return NULL;
+        }
     }
 
     if ((flags12 & SDL12_OPENGLBLIT) == SDL12_OPENGLBLIT) {