Backport c289d6625237 ("Revert "pwm: Set class for exported channels in sysfs"") to 4.19

[John Keeping <john@xxxxxxxxxxxx>]

Hi,

Please consider backporting commit c289d6625237 ("Revert "pwm: Set class
for exported channels in sysfs"") from 4.20 to 4.19 stable (the original
buggy commit was introduced in 4.16).

This one-line revert fixes an oops triggered by writing to sysfs.


Thanks,
John