staging: i4l: act2000: remove extra space

It is not kernel coding style to give an extra space after a cast.
We get warned about it by checkpatch.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>