wifi: rtlwifi: remove unused check_buddy_priv

wifi: rtlwifi: remove unused check_buddy_priv

[ Upstream commit 2fdac64c3c35858aa8ac5caa70b232e03456e120 ]

Commit 2461c7d60f9f ("rtlwifi: Update header file") introduced a global
list of private data structures.

Later on, commit 26634c4b1868 ("rtlwifi Modify existing bits to match
vendor version 2013.02.07") started adding the private data to that list at
probe time and added a hook, check_buddy_priv to find the private data from
a similar device.

However, that function was never used.

Besides, though there is a lock for that list, it is never used. And when
the probe fails, the private data is never removed from the list. This
would cause a second probe to access freed memory.

Remove the unused hook, structures and members, which will prevent the
potential race condition on the list and its corruption during a second
probe when probe fails.

Fixes: 26634c4b1868 ("rtlwifi Modify existing bits to match vendor version 2013.02.07")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20241206173713.3222187-2-cascardo@igalia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>