staging: wilc1000: remove always 'true' check from 'if' statement

Fix few smatch warning related to 'warn: always true condition'.

handle_cfg_param() warn: always true condition
'(cfg_param_attr->auth_timeout < 65536) => (0-u16max < 65536)'
handle_cfg_param() warn: always true condition
'(cfg_param_attr->rts_threshold < 65536) => (0-u16max < 65536)'
handle_cfg_param() warn: always true condition
'(cfg_param_attr->beacon_interval < 65536) => (0-u16max < 65536)'
handle_cfg_param() warn: always true condition
'(cfg_param_attr->site_survey_scan_time < 65536) => (0-u16max <
65536)'
handle_cfg_param() warn: always true condition
'(cfg_param_attr->active_scan_time < 65536) => (0-u16max < 65536)'
handle_cfg_param() warn: always true condition
'(cfg_param_attr->passive_scan_time < 65536) => (0-u16max < 65536)'

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>