ahci: flush dcache before issuing command

Ensure data the following sata command used is flushed out of dcache
and written to physical memory or timeout error may happen.

Signed-off-by: Tang Yuantian <yuantian.tang@nxp.com>

drivers/block/ahci.c

@@ -1061,6 +1061,7 @@ static int ata_io_flush(u8 port)
 
 	memcpy((unsigned char *)pp->cmd_tbl, fis, 20);
 	ahci_fill_cmd_slot(pp, cmd_fis_len);
+	ahci_dcache_flush_sata_cmd(pp);
 	writel_with_flush(1, port_mmio + PORT_CMD_ISSUE);
 
 	if (waiting_for_cmd_completed(port_mmio + PORT_CMD_ISSUE,