[v4, 1/3] ARM: dts: vf610-zii-dev-rev-b: Remove leftover PWM pingroup

[Nikita Yushchenko]

> Remove pwm0grp since it is:
>
>	a) Not referenced anywhere in the DTS file (unlike Tower board it
>	is based on, this board does not use/expose FTM0)
>
>	b) Configures PTB2 and PTB3 in a way that contradicts
>	pinctrl-mdio-mux
>
> Signed-off-by: Andrey Smirnov <andrew.smirnov at gmail.com>

Tested-by: Nikita Yushchenko <nikita.yoush at cogentembedded.com>