rtw88: fix c2h memory leak

Fix erroneous code that leads to unreferenced objects. During H2C
operations, some functions returned without freeing the memory that only
the function have access to. Release these objects when they're no longer
needed to avoid potentially memory leaks.

Signed-off-by: Po-Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210624023459.10294-1-pkshih@realtek.com