Reduce multi-level calls of req.req members

Several places access the members of `req` indirectly like
`req.req.method()`.  This can be simplified as `req.method()` .

This would also make the code clearer.

Tested:
- Compiles
- Redfish service validator passes

Change-Id: Ie129564ff907cdea7ac224b1e3d80cc0dedfbd7b
Signed-off-by: Myung Bae <myungbae@us.ibm.com>
diff --git a/http/http2_connection.hpp b/http/http2_connection.hpp
index 4b1b2dc..8416ff7 100644
--- a/http/http2_connection.hpp
+++ b/http/http2_connection.hpp
@@ -434,7 +434,7 @@
                 close();
                 return -1;
             }
-            thisReq.req.method(verb);
+            thisReq.method(verb);
         }
         else if (nameSv == ":scheme")
         {
@@ -442,7 +442,7 @@
         }
         else
         {
-            thisReq.req.set(nameSv, valueSv);
+            thisReq.addHeader(nameSv, valueSv);
         }
         return 0;
     }