SDL_image: cmake: vendored png target depends on SDL2IMAGE_PNG_SHARED

From af8dc71892669b768b248668db5c61ae57db6859 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Tue, 11 Oct 2022 18:43:53 +0200
Subject: [PATCH] cmake: vendored png target depends on SDL2IMAGE_PNG_SHARED

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9abeefb6..305d9af3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -485,7 +485,7 @@ if(SDL2IMAGE_PNG)
             message(STATUS "${PROJECT_NAME}: Using vendored libpng")
             sdl_check_project_in_subfolder(external/libpng libpng SDL2IMAGE_VENDORED)
             add_subdirectory(external/libpng EXCLUDE_FROM_ALL)
-            if(SDL2IMAGE_BUILD_SHARED_LIBS)
+            if(SDL2IMAGE_PNG_SHARED)
                 set(PNG_LIBRARY png)
             else()
                 set(PNG_LIBRARY png_static)