screen_savers/message: Use delete[] instead of delete

Use delete[] instead of delete, since memory is allocated by new[]
at line 139.

Pointed out by clang.

Change-Id: I70396283b8d2c01d52886f7543804998d891ea44
Reviewed-on: https://review.haiku-os.org/646
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

src/add-ons/screen_savers/message/Message.cpp

@@ -112,7 +112,7 @@ Message::~Message()
 {
 	for (int32 i = 0; i < fFontFamilies.CountItems(); i++) {
 		if (fFontFamilies.ItemAt(i))
-			delete fFontFamilies.ItemAt(i);
+			delete[] fFontFamilies.ItemAt(i);
 	}
 }