phy: phy-bcm-ns2-usbdrd: Replace the deprecated extcon API

This patch replaces the deprecated extcon API as following:
- extcon_set_cable_state_() -> extcon_get_state()

Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>