tcg: Make tb arg to synchronize_from_tb const

There is nothing within the translators that ought to be
changing the TranslationBlock data, so make it const.

This does not actually use the read-only copy of the
data structure that exists within the rx region.

Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/tricore/cpu.c

@@ -42,7 +42,7 @@ static void tricore_cpu_set_pc(CPUState *cs, vaddr value)
 }
 
 static void tricore_cpu_synchronize_from_tb(CPUState *cs,
-                                            TranslationBlock *tb)
+                                            const TranslationBlock *tb)
 {
     TriCoreCPU *cpu = TRICORE_CPU(cs);
     CPUTriCoreState *env = &cpu->env;