ipq806x: remove rpm pinctrl from board dts
These pins seem to be used by hw exclusively, so claiming it in
kernel causes an error in syslog in k4.14+.
Signed-off-by: Pavel Kubelun <[email protected]>
[slh: rebase for kernel v4.14 as well]
Signed-off-by: Stefan Lippers-Hollmann <[email protected]>