staging: vt6655: Rename `by_preamble_type` parameter

Drop Hungarian notation prefix in the first parameter of
`bb_get_frame_time` function. Update the comment to
reflect that change.

Signed-off-by: Karolina Drobnik <karolinadrobnik@gmail.com>
Link: https://lore.kernel.org/r/20211020132326.417059-1-karolinadrobnik@gmail.com


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