mergetools/meld: improve backwards-compatibiilty when using "--output"

Meld 3.16.0 requires a "=" in the --output argument, as it uses a simple hand-rolled command-line parser.

Newer versions of Meld (3.16.4, and possibly earlier) use optparse, which accepts either "--output <file>" or "--output=<file>".

Use "--output=<file>" for better compatibility.

---
Changes since v1:

Fixed an "optpaarse" -> "optparse" typo in the commit message. This patch is otherwise identical to v1.

 mergetools/meld | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index bc178e8882..7a08470f88 100644
@@ -10,7 +10,7 @@ merge_cmd () {
 
 	if test "$meld_has_output_option" = true
 	then
-		"$merge_tool_path" --output "$MERGED" \
+		"$merge_tool_path" --output="$MERGED" \
 			"$LOCAL" "$BASE" "$REMOTE"
 	else
 		"$merge_tool_path" "$LOCAL" "$MERGED" "$REMOTE"

2.13.1.453.gc0395165f3