pinctrl: aspeed: Move aspeed_pin_config_map to separate source file

The AST2600 pinconf differs from the 2400 and 2500, aspeed_pin_config_map
should define separately, and add @confmaps and @nconfmaps to
aspeed_pinctrl_data structure for that change.

Signed-off-by: Johnny Huang <johnny_huang@aspeedtech.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20191202061432.3996-6-andrew@aj.id.au


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>