misc: Replace M5_LOCAL and M5_WEAK with GEM5_LOCAL and GEM5_WEAK.

Change-Id: Ieb8350e647480f9bf582479b7933f0462f18d14d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/45236
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>

src/cpu/testers/traffic_gen/pygen.hh

@@ -45,7 +45,7 @@
 
 struct PyTrafficGenParams;
 
-class M5_LOCAL PyTrafficGen : public BaseTrafficGen
+class GEM5_LOCAL PyTrafficGen : public BaseTrafficGen
 {
   public:
     PyTrafficGen(const PyTrafficGenParams &p);

src/sim/init.cc

@@ -245,7 +245,7 @@ registerNativeModules()
  * Make the commands array weak so that they can be overridden (used
  * by unit tests to specify a different python main function.
  */
-M5_WEAK const char *m5MainCommands[] = {
+GEM5_WEAK const char *m5MainCommands[] = {
     "import m5",
     "m5.main()",
     0 // sentinel is required

src/systemc/core/sc_main_fiber.cc

@@ -38,7 +38,7 @@
 #include "systemc/utils/report.hh"
 
 // A weak symbol to detect if sc_main has been defined, and if so where it is.
-M5_WEAK int sc_main(int argc, char *argv[]);
+GEM5_WEAK int sc_main(int argc, char *argv[]);
 
 namespace sc_gem5
 {