wifi: rtw89: refine rtw89_core_tx_wait_complete()

wifi: rtw89: refine rtw89_core_tx_wait_complete()

Pass TX status value directly into rtw89_core_tx_wait_complete().  This
will make it a bit in sync with further patches and will give flexibility
in future work.  Also use scope based RCU locking which simplifies the
code of the function.

Found by Linux Verification Center (linuxtesting.org).

Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251104135720.321110-5-pchelkin@ispras.ru