rtlwifi: remove assignment to itself

Module parameters of 'sw_crypto' and 'disable_watchdog' are false by
default. If new value is desired, we can do it during inserting module,
assignment existing in source code is not reasonable.

Reported-by: David Binderman <dcb314@hotmail.com>
CC: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>