gtp: small fix: set E if there is an extension header

openair3/ocp-gtpu/gtp_itf.cpp

@@ -184,7 +184,7 @@ static int gtpv1uCreateAndSendMsg(int h,
   // N should be 0 for us (it was used only in 2G and 3G)
   msgHdr->PN=npduNumFlag;
   msgHdr->S=seqNumFlag;
-  msgHdr->E = extHdrType;
+  msgHdr->E = extHdrType != NO_MORE_EXT_HDRS;
   msgHdr->spare=0;
   //PT=0 is for GTP' TS 32.295 (charging)
   msgHdr->PT=1;