accel: Hold @can_reverse information in AccelGdbConfig

Hold @can_reverse in AccelGdbConfig, set it when initializing
AccelState in AccelClass::init_machine handlers (only TCG sets
it). Remove gdb_can_reverse() as now unused.

Signed-off-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-ID: <20260705215729.62196-17-philmd@oss.qualcomm.com>

accel/tcg/tcg-all.c

@@ -159,6 +159,9 @@ static int tcg_init_machine(AccelState *as, MachineState *ms)
          */
         as->gdbstub.sstep_flags |= SSTEP_NOIRQ | SSTEP_NOTIMER;
     }
+    if (replay_mode == REPLAY_MODE_PLAY) {
+        as->gdbstub.can_reverse = true;
+    }
 
     page_init();
     tb_htable_init();