staging: wilc1000: rename strWILC_UsrConnReq of struct host_if_drv

This patch renames strWILC_UsrConnReq of struct host_if_drv to usr_conn_req
to avoid CamelCase naming convention.

Signed-off-by: Leo Kim <leo.kim@atmel.com>
Signed-off-by: Glen Lee <glen.lee@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>