pinctrl: samsung: Remove an always false dev->of_node test

samsung_pinctrl_probe() can be called only after matching
the driver by the compatible string so this already implies
a non null dev->of_node.  Remove the always false test
and related error trace. While at it drop another error log
in case of memory allocation failure - any errors are logged
by the memory subsystem.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>