rtlwifi: Convert individual interrupt results to struct

With the RTL8822BE and later devices, the number of interrupt vectors
has grown from 2 to 4. At this point, saving and passing those vectors
in a struct makes more sense than using individual scaler variables.

In two of the drivers, code to process the second of the interrupt
registers was included, but commented out. This patch removes those
useless sections.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>