pinctrl: handle zero found dt pinconfig properties better

This adds a shortcut when no valid pinconf properties are found
in the parsed dt node, to set the values immediately and return.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git


Git-commit: e4a8844c04c00a1a64c6779692e1b
Change-Id: I513d4df0857864c8e5d4813905bd23410be37ad4
Signed-off-by: Hanumant Singh <hanumant@codeaurora.org>