drivers: pinctrl: Remove duplicate include of io.h

linux/io.h has been included at line 6, so remove the
duplicate include at line 18.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Link: https://lore.kernel.org/r/20210323013727.135571-1-wanjiabing@vivo.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-k210.c

@@ -15,7 +15,6 @@
 #include <linux/pinctrl/pinmux.h>
 #include <linux/pinctrl/pinconf.h>
 #include <linux/pinctrl/pinconf-generic.h>
-#include <linux/io.h>
 
 #include <dt-bindings/pinctrl/k210-fpioa.h>