staging: r8188eu: Remove uninitialized use of ether_type in portctrl()

staging: r8188eu: Remove uninitialized use of ether_type in portctrl()

After commit 987219ad34a6 ("staging: r8188eu: remove lines from Makefile
that silence build warnings"), clang warns:

drivers/staging/r8188eu/core/rtw_recv.c:499:8: warning: variable
'ether_type' is uninitialized when used here [-Wuninitialized]
                        if (ether_type == eapol_type)
                            ^~~~~~~~~~
drivers/staging/r8188eu/core/rtw_recv.c:458:16: note: initialize the
variable 'ether_type' to silence this warning
        u16     ether_type;
                          ^
                           = 0
1 warning generated.

This if statement sets the exact same assignment as above so just remove
it.

Acked-by: Phillip Potter <phil@philpotter.co.uk>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20210812204027.338872-3-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>