macos: extractloop.sh: exclude symlink & mute ln error message
macos: extractloop.sh: exclude symlink & mute ln error message

Extracting the symlink fails with

	linux-3.0/arch/microblaze/boot/dts/system.dts: Can't set permissions to 0755

so just exclude it.

The ln error Looks scary but is harmless, so get rid of it.
The symlink is only created to make it more convenient to view the
csv log.

rfjakob/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs,rfjakob/gocryptfs