staging: rtl8723bs: fix null dereference in find_network

staging: rtl8723bs: fix null dereference in find_network

[ Upstream commit 41460a19654c32d39fd0e3a3671cd8d4b7b8479f ]

The variable pwlan has the possibility of being NULL when passed into
rtw_free_network_nolock() which would later dereference the variable.

Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable@vger.kernel.org
Signed-off-by: Ethan Tidmore <ethantidmore06@gmail.com>
Link: https://patch.msgid.link/20260202205429.20181-1-ethantidmore06@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>