rtw88: fix memory overrun and memory leak during hw_scan

rtw88: fix memory overrun and memory leak during hw_scan

[ Upstream commit d95984b5580dcb8b1c0036577c52b609990a1dab ]

Previously we allocated less memory than actual required, overwrite
to the buffer causes the mm module to complaint and raise access
violation faults. Along with potential memory leaks when returned
early. Fix these by passing the correct size and proper deinit flow.

Fixes: 10d162b2ed39 ("rtw88: 8822c: add ieee80211_ops::hw_scan")
Signed-off-by: Po-Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220121070813.9656-4-pkshih@realtek.com
Signed-off-by: Sasha Levin <sashal@kernel.org>