The name field in structure i2c_device_id is 20 characters, and we expect
it to be NULL-terminated, however we are trying to stuff it with 21 bytes
and thus NULL-terminator is lost. This causes issues when one creates
device with name "MICROCHIP_AR1021_I2C" as i2c core cuts off the last "C",
and automatic module loading by alias does not work as result.

The -I2C suffix in the device name is superfluous, we know what bus we are
dealing with, so let's drop it. Also, no other driver uses capitals, and
the manufacturer name is normally not included, except in very rare cases
of incompatible name collisions.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116211
Fixes: dd4cae8b ("Input: Add Microchip AR1021 i2c touchscreen")
Reviewed-By: Christian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>