net: phy: meson-gxl: make function meson_gxl_read_status static

The function meson_gxl_read_status is local to the source and does
not need to be in global scope, so make it static.

Cleans up sparse warning:
symbol 'meson_gxl_read_status' was not declared. Should it be static?
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NJerome Brunet <jbrunet@baylibre.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/phy/meson-gxl.c

@@ -67,7 +67,7 @@ static int meson_gxl_config_init(struct phy_device *phydev)
  * When this failure happens, the first retry is usually successful but,
  * in some cases, it may take up to 6 retries to get a decent result
  */
-int meson_gxl_read_status(struct phy_device *phydev)
+static int meson_gxl_read_status(struct phy_device *phydev)
 {
 	int ret, wol, lpa, exp;