[DTV00857290][DTV][Coverity Scanned Code Defect]

[Description]
Fix coverity defects under nic/nic_rate.c

Fix Uninitialized scalar variable
 - Cid#361785 in line 411
 - Cid#361786 in line 415

Change-Id: I9893058c93360d641b9db1551aa609d441c23d22
Signed-off-by: Alice Ou <alice.ou@mediatek.com>
CR-Id: DTV00857290
(cherry picked from commit 53deb4db2b84c6d71eedb65b76c9d60534761192)
(cherry picked from commit 07154a7fbc401ba110190313979e38e8aec08ea1)
(cherry picked from commit 7264436c1cf9b361682b8fa680ece35388ca7490)
diff --git a/nic/nic_rate.c b/nic/nic_rate.c
index b592c7f..938a3ed 100644
--- a/nic/nic_rate.c
+++ b/nic/nic_rate.c
@@ -408,22 +408,21 @@
 			u4CurPhyRate =
 				nicRateCode2DataRate(u2CurRateCode, MAC_BW_20, MAC_GI_NORMAL);
 
-			if (u4HighestPhyRate < u4CurPhyRate) {
-				u4HighestPhyRate = u4CurPhyRate;
-				ucHighestPhyRateSwIdx = i;
-			}
-			if (u4LowestPhyRate > u4CurPhyRate) {
-				u4LowestPhyRate = u4CurPhyRate;
-				ucLowestPhyRateSwIdx = i;
-			}
-
 			/* Compare */
 			if (fgGetLowest) {
+				if (u4HighestPhyRate < u4CurPhyRate) {
+					u4HighestPhyRate = u4CurPhyRate;
+					ucHighestPhyRateSwIdx = i;
+				}
 				if ((u4CurPhyRate >= u4PhyRateLimit) && (u4CurPhyRate <= u4TarPhyRate)) {
 					u4TarPhyRate = u4CurPhyRate;
 					ucTarRateSwIndex = i;
 				}
 			} else {
+				if (u4LowestPhyRate > u4CurPhyRate) {
+					u4LowestPhyRate = u4CurPhyRate;
+					ucLowestPhyRateSwIdx = i;
+				}
 				if ((u4CurPhyRate <= u4PhyRateLimit) && (u4CurPhyRate >= u4TarPhyRate)) {
 					u4TarPhyRate = u4CurPhyRate;
 					ucTarRateSwIndex = i;