[SEBA-660] : Adding Igmp support in BbSim

Change-Id: I9f5c7d8ad39ac82850b04e2c997996d6c47b32d2
diff --git a/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
index 11be7cd..ae6c897 100644
--- a/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
+++ b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
@@ -25,40 +25,14 @@
 )
 
 const (
-	prefix              = "GRPC_GO_"
-	retryStr            = prefix + "RETRY"
-	requireHandshakeStr = prefix + "REQUIRE_HANDSHAKE"
-)
-
-// RequireHandshakeSetting describes the settings for handshaking.
-type RequireHandshakeSetting int
-
-const (
-	// RequireHandshakeOn indicates to wait for handshake before considering a
-	// connection ready/successful.
-	RequireHandshakeOn RequireHandshakeSetting = iota
-	// RequireHandshakeOff indicates to not wait for handshake before
-	// considering a connection ready/successful.
-	RequireHandshakeOff
+	prefix          = "GRPC_GO_"
+	retryStr        = prefix + "RETRY"
+	txtErrIgnoreStr = prefix + "IGNORE_TXT_ERRORS"
 )
 
 var (
 	// Retry is set if retry is explicitly enabled via "GRPC_GO_RETRY=on".
 	Retry = strings.EqualFold(os.Getenv(retryStr), "on")
-	// RequireHandshake is set based upon the GRPC_GO_REQUIRE_HANDSHAKE
-	// environment variable.
-	//
-	// Will be removed after the 1.18 release.
-	RequireHandshake = RequireHandshakeOn
+	// TXTErrIgnore is set if TXT errors should be ignored ("GRPC_GO_IGNORE_TXT_ERRORS" is not "false").
+	TXTErrIgnore = !strings.EqualFold(os.Getenv(retryStr), "false")
 )
-
-func init() {
-	switch strings.ToLower(os.Getenv(requireHandshakeStr)) {
-	case "on":
-		fallthrough
-	default:
-		RequireHandshake = RequireHandshakeOn
-	case "off":
-		RequireHandshake = RequireHandshakeOff
-	}
-}