staging: vt6655: Remove unnecessary type casts

Remove casts to unsigned short in `RFvWriteWakeProgSyn` function as they are
not needed.

Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Karolina Drobnik <karolinadrobnik@gmail.com>
Link: https://lore.kernel.org/r/c9a5718479deda078b582cbc42a4e7b2f3a6cb39.1636729147.git.karolinadrobnik@gmail.com


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