UPSTREAM: pwm: Add information about polarity, duty cycle and period to debugfs

UPSTREAM: pwm: Add information about polarity, duty cycle and period to debugfs

The PWM states make it possible to also output the polarity, duty cycle
and period information in the debugfs summary output. This simplifies
gathering information about PWMs without needing to walk through the
sysfs attributes of every PWM.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[thierry.reding@gmail.com: use more spaces in debugfs output]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit 23e3523f5d3a980edf7f189743cf4bb9490400a9)

Change-Id: Ia5d4d9ab898510d07364ad455ccf93e1c1d95d2b
Signed-off-by: David Wu <david.wu@rock-chips.com>