staging: rtl8712: cmd: remove redundant space after cast

Remove the unnecessary space immediately after a cast. Identified by
checkpatch: CHECK: No space is necessary after a cast.

Signed-off-by: Aliya Rahmani <aliyarahmani786@gmail.com>
Link: https://lore.kernel.org/r/20220413113531.31224-1-aliyarahmani786@gmail.com


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