NetworkPkg: Update HttpDxe driver to consume EFI_HTTP_UTILITIES_PROTOCOL

v2:
* Register a notification function to be executed for Http utilities protocol
in the drivers entry points.

Since we add EFI_HTTP_UTILITIES_PROTOCOL support, HttpDxe driver should
be updated to remove internal http utilities functions and consume this
protocol directly.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Cc: Samer El-Haj-Mahmoud <elhaj@hp.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18316 6f19259b-4bc3-4df7-8a09-765794883524

NetworkPkg/HttpDxe/HttpProto.c

@@ -1071,19 +1071,27 @@ HttpGenRequestString (
     AppendList[Index] = &Message->Headers[Index];
   }
 
+  //
+  // Check whether the EFI_HTTP_UTILITIES_PROTOCOL is available.
+  //
+  if (mHttpUtilities == NULL) {
+    return NULL;
+  }
+
   //
   // Build raw unformatted HTTP headers.
-  //  
-  Status = HttpUtilitiesBuild (
-             0,
-             NULL,
-             0,
-             NULL,
-             Message->HeaderCount,
-             AppendList,
-             &HttpHdrSize,
-             &HttpHdr
-             );
+  //
+  Status = mHttpUtilities->Build (
+                             mHttpUtilities,
+                             0,
+                             NULL,
+                             0,
+                             NULL,
+                             Message->HeaderCount,
+                             AppendList,
+                             &HttpHdrSize,
+                             &HttpHdr
+                             );
   FreePool (AppendList);
   if (EFI_ERROR (Status) || HttpHdr == NULL) {
     return NULL;