drivers: net: smc91x: Fix missing kerneldoc reported by W=1

drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'dev' not described in 'try_toggle_control_gpio'
drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'desc' not described in 'try_toggle_control_gpio'
drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'name' not described in 'try_toggle_control_gpio'
drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'index' not described in 'try_toggle_control_gpio'
drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'value' not described in 'try_toggle_control_gpio'
drivers/net/ethernet/smsc/smc91x.c:2199: warning: Function parameter or member 'nsdelay' not described in 'try_toggle_control_gpio'

Document these parameters.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>