misc: Substitute pointer to Request with aliased RequestPtr

Every usage of Request* in the code has been replaced with the
RequestPtr alias.  This is a preparing patch for when RequestPtr will be
the typdefed to a smart pointer to Request rather then a raw pointer to
Request.

Change-Id: I73cbaf2d96ea9313a590cdc731a25662950cd51a
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10995
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

src/cpu/checker/cpu.cc

@@ -337,7 +337,7 @@ CheckerCPU::dbg_vtophys(Addr addr)
  * Checks if the flags set by the Checker and Checkee match.
  */
 bool
-CheckerCPU::checkFlags(Request *unverified_req, Addr vAddr,
+CheckerCPU::checkFlags(RequestPtr unverified_req, Addr vAddr,
                        Addr pAddr, int flags)
 {
     Addr unverifiedVAddr = unverified_req->getVaddr();