thunderbolt: Fix typos in documentation comments

Fixes two minor typos in Thunderbolt driver comments:
Correct "passwd" -> "passed" in nvm.c.
Correct "boths" -> "both" in switch.c.

Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>