staging: r8188eu: stop beacon processing if kmalloc fails

staging: r8188eu: stop beacon processing if kmalloc fails

If we cannot allocate a struct wlan_bssid_ex in the OnBeacon function, we
should stop processing the incoming beacon message and return.

For kmalloc failures, the current code just skips the update of network
and beacon info and tries to continue with the authentication. The update
would set the encryption algorithm that should be used for the
authentication.

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/20221126160129.178697-9-martin@kaiser.cx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>