staging: r8188eu: exit if beacon is not from our bss

staging: r8188eu: exit if beacon is not from our bss

Do not process an incoming beacon message in the OnBeacon function if the
beacon was sent by a base station other than the one to which we're
connected.

This patch does not modify the behaviour of the code. It reverts the if
condition and returns if the beacon should not be processed. This is
simpler than wrapping the entire processing into a large if clause.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20221126160129.178697-8-martin@kaiser.cx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>