dev: Remove TheISA from ns_gige.cc.

It was not being used there.

Change-Id: Ib39cfb52553e0556f7a6ad616e1029c74fa90e1f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22271
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

src/dev/net/ns_gige.cc

@@ -43,7 +43,6 @@
 #include "base/debug.hh"
 #include "base/inet.hh"
 #include "base/types.hh"
-#include "config/the_isa.hh"
 #include "debug/EthernetAll.hh"
 #include "dev/net/etherlink.hh"
 #include "mem/packet.hh"
@@ -90,7 +89,6 @@ const char *NsDmaState[] =
 };
 
 using namespace Net;
-using namespace TheISA;
 
 ///////////////////////////////////////////////////////////////////////
 //