net: stmmac: dwmac-meson8b: Add support for the Meson8m2 SoC

The Meson8m2 SoC uses a similar (potentially even identical) register
layout as the Meson8b and GXBB SoCs for the dwmac glue.
Add a new compatible string and update the module description to
indicate support for these SoCs.
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c

 /*
- * Amlogic Meson8b and GXBB DWMAC glue layer
+ * Amlogic Meson8b, Meson8m2 and GXBB DWMAC glue layer
  *
  * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
  *
@@ -318,6 +318,7 @@ static int meson8b_dwmac_probe(struct platform_device *pdev)
 
 static const struct of_device_id meson8b_dwmac_match[] = {
 	{ .compatible = "amlogic,meson8b-dwmac" },
+	{ .compatible = "amlogic,meson8m2-dwmac" },
 	{ .compatible = "amlogic,meson-gxbb-dwmac" },
 	{ }
 };
@@ -335,5 +336,5 @@ static struct platform_driver meson8b_dwmac_driver = {
 module_platform_driver(meson8b_dwmac_driver);
 
 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
-MODULE_DESCRIPTION("Amlogic Meson8b and GXBB DWMAC glue layer");
+MODULE_DESCRIPTION("Amlogic Meson8b, Meson8m2 and GXBB DWMAC glue layer");
 MODULE_LICENSE("GPL v2");