HID: sony: remove redundant assignment

The variable ret is being assigned a value that is never read
afterwards. The assignment is redundant and can be removed.

Cleans up clang scan build warning:
drivers/hid/hid-sony.c:2020:3: warning: Value stored to 'ret'
is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>