status_led: don't display errors while reading CPLD values
status_led: don't display errors while reading CPLD values

Do not display errors from attempting to read/write CPLD-sourced values
that do not exist on all NI Linux-RT targets

Signed-off-by: Joshua Hernstrom <32dc8cfec5c07c8b12607232c3deac1c85064218@ni.com>
Acked-by: Bill Pittman <43ac99c9c99efa205ddaaebf4c7bd970d58e135c@ni.com>
Acked-by: Brad Mouring <58d99a887450796456131638ba4c43b5ba95afcf@ni.com>

ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt