usb: typec: tps6598x: Fix build error without CONFIG_REGMAP_I2C

If CONFIG_REGMAP_I2C is not set, building fails:

drivers/usb/typec/tps6598x.o: In function `tps6598x_probe':
tps6598x.c:(.text+0x5f0): undefined reference to `__devm_regmap_init_i2c'

Select REGMAP_I2C to fix this.
Reported-by: NHulk Robot <hulkci@huawei.com>
Fixes: 0a4c005b ("usb: typec: driver for TI TPS6598x USB Power Delivery controllers")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Acked-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20190903121026.22148-1-yuehaibing@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/Kconfig

@@ -53,6 +53,7 @@ source "drivers/usb/typec/ucsi/Kconfig"
 config TYPEC_TPS6598X
 	tristate "TI TPS6598x USB Power Delivery controller driver"
 	depends on I2C
+	select REGMAP_I2C
 	help
 	  Say Y or M here if your system has TI TPS65982 or TPS65983 USB Power
 	  Delivery controller.