gpio: mockup: be quiet unless something goes wrong

When inserting and removing the module repeatedly (e.g. when running
the libgpiod test-suite) the kernel log gets clobbered with messages
reporting successful creation of dummy gpiochips.

Remove this message and only emit logs when something bad happens.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-mockup.c

@@ -364,9 +364,6 @@ static int gpio_mockup_probe(struct platform_device *pdev)
 
 			return ret;
 		}
-
-		dev_info(dev, "gpio<%d..%d> add successful!",
-			 base, base + ngpio);
 	}
 
 	return 0;