Add Support for samsung wireless keyboard with input mapping events.

Device 7021 (Samsung wireless keyboard).
Signed-off-by: Sandeep C S <sandeep.cs@samsung.com>
Signed-off-by: Junwan Cho <junwan.cho@samsung.com>
Signed-off-by: Jitender Sajwan <jitender.s21@samsung.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>