arch-sparc: Create a local port proxy for functional accesses.

Don't retrieve one from the thread context since it's just as easy to
make one from scratch.

Change-Id: I46a812df656a553cc0bd94f61a371b595412a9b3
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/45904
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>

src/arch/sparc/tlb.cc

@@ -897,7 +897,7 @@ TLB::translateFunctional(const RequestPtr &req, ThreadContext *tc, Mode mode)
     if (!FullSystem)
         return tc->getProcessPtr()->pTable->translate(req);
 
-    PortProxy &mem = tc->getPhysProxy();
+    PortProxy mem(tc, tc->getSystemPtr()->cacheLineSize());
     // We didn't find it in the tlbs, so lets look at the TSBs
     GetTsbPtr(tc, vaddr, ctx_zero ? 0 : pri_context, tsbs);
     va_tag = bits(vaddr, 63, 22);