staging: r8188eu: drop redundant if check in IS_MCAST

The if check is redundant. Drop it and simplify the funciton.

Signed-off-by: Vihas Makwana <makvihas@gmail.com>
Link: https://lore.kernel.org/r/20220405124239.3372-2-makvihas@gmail.com


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