[][Fix coverity scan check errors in mtk eth driver]

[Description]
Fix coverity scan check errors in mtk eth driver

[Release-log]
N/A

Change-Id: Idd57117afcc0478c107ef0e683a4993eb80221c0
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5108909
diff --git a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_sgmii.c b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_sgmii.c
index 2785666..50bdbd8 100755
--- a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_sgmii.c
+++ b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_sgmii.c
@@ -37,7 +37,7 @@
 	return 0;
 }
 
-int mtk_sgmii_setup_mode_an(struct mtk_sgmii *ss, int id)
+int mtk_sgmii_setup_mode_an(struct mtk_sgmii *ss, unsigned int id)
 {
 	unsigned int val;
 
@@ -67,7 +67,7 @@
 	return 0;
 }
 
-int mtk_sgmii_setup_mode_force(struct mtk_sgmii *ss, int id,
+int mtk_sgmii_setup_mode_force(struct mtk_sgmii *ss, unsigned int id,
 			       const struct phylink_link_state *state)
 {
 	unsigned int val;