w1_therm: remove redundant assignments to variable ret

w1_therm: remove redundant assignments to variable ret

commit f37d13d52c0560bd2bac40b22466af538e61a5ce upstream.

The variable ret is being initialized with a value that is never read
and it is being updated later with a new value. The initialization
is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200519154553.873413-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>