atl1c: clear bit MASTER_CTRL_CLK_SEL_DIS in atl1c_pcie_patch

bit MASTER_CTRL_CLK_SEL_DIS could be set before enter suspend
clear it after resume to enable pclk(PCIE clock) switch to
low frequency(25M) in some circumstances to save power.
Signed-off-by: Nxiong <xiong@qca.qualcomm.com>
Tested-by: NLiu David <dwliu@qca.qualcomm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/atheros/atl1c/atl1c_main.c

@@ -80,7 +80,12 @@ static const u32 atl1c_default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
 	NETIF_MSG_LINK | NETIF_MSG_TIMER | NETIF_MSG_IFDOWN | NETIF_MSG_IFUP;
 static void atl1c_pcie_patch(struct atl1c_hw *hw)
 {
-	u32 data;
+	u32 mst_data, data;
+
+	/* pclk sel could switch to 25M */
+	AT_READ_REG(hw, REG_MASTER_CTRL, &mst_data);
+	mst_data &= ~MASTER_CTRL_CLK_SEL_DIS;
+	AT_WRITE_REG(hw, REG_MASTER_CTRL, mst_data);
 
 	AT_READ_REG(hw, REG_PCIE_PHYMISC, &data);
 	data |= PCIE_PHYMISC_FORCE_RCV_DET;