rwops: Use SetFilePointerEx on Windows for appending writes.

Fixes #7900.

(cherry picked from commit 769bf2ebcca8f0cbcde4ec50008942f4eda57f4a)
diff --git a/src/file/SDL_rwops.c b/src/file/SDL_rwops.c
index e5a1674..87307ab 100644
--- a/src/file/SDL_rwops.c
+++ b/src/file/SDL_rwops.c
@@ -277,8 +277,9 @@
 
     /* if in append mode, we must go to the EOF before write */
     if (context->hidden.windowsio.append) {
-        if (SetFilePointer(context->hidden.windowsio.h, 0L, NULL, FILE_END) ==
-            INVALID_SET_FILE_POINTER) {
+        LARGE_INTEGER windowsoffset;
+        windowsoffset.QuadPart = 0;
+        if (!SetFilePointerEx(context->hidden.windowsio.h, windowsoffset, &windowsoffset, FILE_END)) {
             SDL_Error(SDL_EFWRITE);
             return 0;
         }