pinctrl: sdm660: Set tile property for pingroups

This was missed when tiles support was added in a revison and
causes the driver to fail to load.

Fixes: 9cf0c526 ("pinctrl: qcom: Add sdm660 pinctrl driver")
Signed-off-by: Craig Tatlor <ctatlor97@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>