HID: magicmouse: simplify multitouch feature request

Only the first feature request is required to put the Magic Mouse into
multitouch mode. This is also the case for the Magic Trackpad, for which
support will be added in a later commit.

Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Acked-by: Michael Poole <mdpoole@troilus.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>