HID: microsoft: no fallthrough in MS ergonomy 0xff05 usage

For 0xff05 usage in MS ergonomy keyboard quirk, we are falling through
and returning 0 instread of properly (because we've performed new mapping)
returning 1. Fix that.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>