net: phy: cortina: Staticize PHY driver entries

These struct phy_driver ... instances are local to this source code
file, staticize them. No functional change.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Acked-by: Michal Simek <michal.simek@amd.com>
Tested-by: Michal Simek <michal.simek@amd.com> #microblaze (MANUAL_RELOC)
diff --git a/drivers/net/phy/cortina.c b/drivers/net/phy/cortina.c
index 778d93e..df5a73d 100644
--- a/drivers/net/phy/cortina.c
+++ b/drivers/net/phy/cortina.c
@@ -382,7 +382,7 @@
 	return 0;
 }
 
-struct phy_driver cs4340_driver = {
+static struct phy_driver cs4340_driver = {
 	.name = "Cortina CS4315/CS4340",
 	.uid = PHY_UID_CS4340,
 	.mask = 0xfffffff0,
@@ -396,7 +396,7 @@
 	.shutdown = &gen10g_shutdown,
 };
 
-struct phy_driver cs4223_driver = {
+static struct phy_driver cs4223_driver = {
 	.name = "Cortina CS4223",
 	.uid = PHY_UID_CS4223,
 	.mask = 0x0ffff00f,