UPSTREAM: usb: typec: mux: remove redundant check on variable match

All the code paths that lead to the return statement are where
match is always true, hence the check to see if it is true is
redundant and can be removed.

Detected by CoverityScan, CID#14769672 ("Logically dead code")

Bug: 150877929
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: Iedfd85df7b0719ff0b9dc4431188850921157e57
Signed-off-by: Will McVicker <willmcvicker@google.com>
(cherry picked from commit eb76b37aaf7e6bdd6638bf5b2ef29688645e03b8)