staging: r8822be: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtlwifi/halmac/halmac_88xx/halmac_api_88xx.c

@@ -3391,8 +3391,10 @@ halmac_cfg_txbf_88xx(struct halmac_adapter *halmac_adapter, u8 userid,
 		switch (bw) {
 		case HALMAC_BW_80:
 			temp42C |= BIT_R_TXBF0_80M;
+			/* fall through */
 		case HALMAC_BW_40:
 			temp42C |= BIT_R_TXBF0_40M;
+			/* fall through */
 		case HALMAC_BW_20:
 			temp42C |= BIT_R_TXBF0_20M;
 			break;