net: stmmac: Rename clk_ptp_ref clock to ptp_ref

There aren't currently any users of the "clk_ptp_ref", but there are
other references to "ptp_ref", so I'm leaning towards considering that a
typo. Fix it.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/stmmac.txt

@@ -28,9 +28,9 @@ Optional properties:
   clocks may be specified in derived bindings.
 - clock-names: One name for each entry in the clocks property, the
   first one should be "stmmaceth" and the second one should be "pclk".
-- clk_ptp_ref: this is the PTP reference clock; in case of the PTP is
-  available this clock is used for programming the Timestamp Addend Register.
-  If not passed then the system clock will be used and this is fine on some
+- ptp_ref: this is the PTP reference clock; in case of the PTP is available
+  this clock is used for programming the Timestamp Addend Register. If not
+  passed then the system clock will be used and this is fine on some
   platforms.
 - tx-fifo-depth: See ethernet.txt file in the same directory
 - rx-fifo-depth: See ethernet.txt file in the same directory

drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c

@@ -359,7 +359,7 @@ stmmac_probe_config_dt(struct platform_device *pdev, const char **mac)
 	clk_prepare_enable(plat->pclk);
 
 	/* Fall-back to main clock in case of no PTP ref is passed */
-	plat->clk_ptp_ref = devm_clk_get(&pdev->dev, "clk_ptp_ref");
+	plat->clk_ptp_ref = devm_clk_get(&pdev->dev, "ptp_ref");
 	if (IS_ERR(plat->clk_ptp_ref)) {
 		plat->clk_ptp_rate = clk_get_rate(plat->stmmac_clk);
 		plat->clk_ptp_ref = NULL;