SDL_rtf: Fix 'retval' may be used uninitialized [-Werror=maybe-uninitialized] (752ac)

From 752acd16f884a8b1edfa84ff6433050fc8813609 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Mon, 15 Jan 2024 18:54:08 +0100
Subject: [PATCH] Fix 'retval' may be used uninitialized
 [-Werror=maybe-uninitialized]

(cherry picked from commit 5832e3a29971c2b12ff899037c98959a4c699a94)
---
 SDL_rtf.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/SDL_rtf.c b/SDL_rtf.c
index fe5ad7a..4f96878 100644
--- a/SDL_rtf.c
+++ b/SDL_rtf.c
@@ -125,6 +125,10 @@ int RTF_Load_RW(RTF_Context *ctx, SDL_RWops *src, int freesrc)
             RTF_SetError("Couldn't find font for text");
             retval = -1;
             break;
+        default:
+            RTF_SetError("Unknown error");
+            retval = -1;
+            break;
     }
     while ( ctx->psave ) {
         ecPopRtfState(ctx);