HID: wacom: Re-enable touch by default for Cintiq 24HDT / 27QHDT

Commit 670e9092 ("HID: wacom: support named keys on older devices")
added support for sending named events from the soft buttons on the
24HDT and 27QHDT. In the process, however, it inadvertantly disabled the
touchscreen of the 24HDT and 27QHDT by default. The
`wacom_set_shared_values` function would normally enable touch by default
but because it checks the state of the non-shared `has_mute_touch_switch`
flag and `wacom_setup_touch_input_capabilities` sets the state of the
/shared/ version, touch ends up being disabled by default.

This patch sets the non-shared flag, letting `wacom_set_shared_values`
take care of copying the value over to the shared version and setting
the default touch state to "on".

Fixes: 670e9092 ("HID: wacom: support named keys on older devices")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Ping Cheng <ping.cheng@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>