linux-phytec-fsl

extcon: Remove optional print_state() function pointer of struct extcon_dev

This patch removes the optional print_state() function pointer which included
in 'struct extcon_dev' because the extcon must maintain the consistent name
of extcon device on sysfs instead of inconsistent state of external connectors.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>