SDL: Use GNU sed if available (d649f)

SDL Commits
1 
From d649f957233014b1e1a46ad1d505699e1bc1c320 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Mon, 6 Feb 2023 15:47:16 -0800
Subject: [PATCH] Use GNU sed if available

Fixes update-copyright.sh on macOS, which doesn't support the -b option.

(cherry picked from commit a357021800b4af2b850476bcd87be5648923b847)
---
 build-scripts/update-copyright.sh | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/build-scripts/update-copyright.sh b/build-scripts/update-copyright.sh
index 574d904253e9..9bb46eac5b2f 100755
--- a/build-scripts/update-copyright.sh
+++ b/build-scripts/update-copyright.sh
@@ -1,7 +1,15 @@
 #!/bin/sh
 
+if [ "$SED" = "" ]; then
+    if type gsed >/dev/null; then
+        SED=gsed
+    else
+        SED=sed
+    fi
+fi
+
 find . -type f \
 | grep -v \.git                                 \
 | while read file; do                           \
-    LC_ALL=C sed -b -i "s/\(.*Copyright.*\)[0-9]\{4\}\( *Sam Lantinga\)/\1`date +%Y`\2/" "$file"; \
+    LC_ALL=C $SED -b -i "s/\(.*Copyright.*\)[0-9]\{4\}\( *Sam Lantinga\)/\1`date +%Y`\2/" "$file"; \
 done