systemc: Stop using the sc_string_view type.

It doesn't seem to provide anything more that std::string, and comes
with extra dependencies/baggage.

Change-Id: I2c599bcc93fa4a944ff249410d24e8f8be981afe
Reviewed-on: https://gem5-review.googlesource.com/c/15298
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

src/systemc/tlm_core/2/generic_payload/phase.cc

@@ -19,12 +19,11 @@
 
 #include <cstring>
 #include <map>
+#include <string>
 #include <systemc>
 #include <tlm>
 #include <typeindex>
 
-using sc_core::sc_string_view;
-
 namespace tlm
 {
 
@@ -43,7 +42,7 @@ struct tlm_phase_registry
     }
 
     unsigned int
-    register_phase(std::type_index type, sc_string_view name)
+    register_phase(std::type_index type, std::string name)
     {
         type_map::const_iterator it = ids_.find(type);