tty: vt: add new helper for reseting vc parameters

The code to reset the vc parameter parsing is repeated on two locations.
Create a helper vc_reset_params() and use it on both of them.

And instead of a 'for' loop to clear the array of parameters, use
simpler memset().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240202065608.14019-19-jirislaby@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>