libertas: Remove unnecessary label of lbs_ethtool_get_eeprom

The label is only used once, so we delete it and use the
return statement instead of the goto statement.

Signed-off-by: dingsenjie <dingsenjie@yulong.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210625121108.162868-1-dingsenjie@163.com