SDL: Adding a clarifying comment in case a programmer unfamiliar with UTF-16 and UTF-32's relationship chances upon the code.

SDL Commits
1 
From cb0fd05eebf49f7c463e9f1763afee424191a64c Mon Sep 17 00:00:00 2001
From: hgs3 <[EMAIL REDACTED]>
Date: Sat, 7 Aug 2021 22:41:54 -0500
Subject: [PATCH] Adding a clarifying comment in case a programmer unfamiliar
 with UTF-16 and UTF-32's relationship chances upon the code.

---
 src/video/windows/SDL_windowsevents.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/video/windows/SDL_windowsevents.c b/src/video/windows/SDL_windowsevents.c
index 1aafd7a90..555f9b226 100644
--- a/src/video/windows/SDL_windowsevents.c
+++ b/src/video/windows/SDL_windowsevents.c
@@ -898,7 +898,8 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
             }
             data->high_surrogate = 0;
         } else {
-            /* The code point is in the Basic Multilingual Plane */
+            /* The code point is in the Basic Multilingual Plane.
+               It's numerically equal to UTF-32. */
             char text[5];
             if (WIN_ConvertUTF32toUTF8((UINT32)wParam, text)) {
                 SDL_SendKeyboardText(text);