linux-phytec-ti

extcon: gpio: Use devm_extcon_dev_allocate for extcon_dev

This patch use devm_extcon_dev_allocate() to simplify the memory control
of extcon device.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>