staging: qlge: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-throughSigned-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200727184042.GA29074@embeddedorSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/qlge/qlge_mpi.c

@@ -1174,7 +1174,7 @@ void ql_mpi_idc_work(struct work_struct *work)
 	case MB_CMD_PORT_RESET:
 	case MB_CMD_STOP_FW:
 		ql_link_off(qdev);
-		/* Fall through */
+		fallthrough;
 	case MB_CMD_SET_PORT_CFG:
 		/* Signal the resulting link up AEN
 		 * that the frame routing and mac addr
@@ -1207,7 +1207,7 @@ void ql_mpi_idc_work(struct work_struct *work)
 		 */
 		ql_link_off(qdev);
 		set_bit(QL_CAM_RT_SET, &qdev->flags);
-		/* Fall through. */
+		fallthrough;
 	case MB_CMD_IOP_DVR_START:
 	case MB_CMD_IOP_FLASH_ACC:
 	case MB_CMD_IOP_CORE_DUMP_MPI: