download.dl: fix @KERNEL mirror urls

- Prepend "/pub" for mirror.rackspace.com
 - Use https for download.xs4all.nl and mirrors.mit.edu

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

scripts/download.pl

@@ -231,12 +231,12 @@ foreach my $mirror (@ARGV) {
 			push @extra, "$extra[0]/testing";
 		} elsif ($filename =~ /linux-(\d+\.\d+(?:\.\d+)?)/) {
 			push @extra, "$extra[0]/longterm/v$1";
-		}		
+		}
 		foreach my $dir (@extra) {
 			push @mirrors, "https://cdn.kernel.org/pub/$dir";
-			push @mirrors, "https://mirror.rackspace.com/kernel.org/$dir";
-			push @mirrors, "http://download.xs4all.nl/ftp.kernel.org/pub/$dir";
-			push @mirrors, "http://mirrors.mit.edu/kernel/$dir";
+			push @mirrors, "https://mirror.rackspace.com/kernel.org/pub/$dir";
+			push @mirrors, "https://download.xs4all.nl/ftp.kernel.org/pub/$dir";
+			push @mirrors, "https://mirrors.mit.edu/kernel/$dir";
 			push @mirrors, "http://ftp.nara.wide.ad.jp/pub/kernel.org/$dir";
 			push @mirrors, "http://www.ring.gr.jp/archives/linux/kernel.org/$dir";
 			push @mirrors, "ftp://ftp.riken.jp/Linux/kernel.org/$dir";