Prevents abort with m68K (#1012)

* Prevents abort with m68K

Raises exception instead

* M68K remove one uses of abort

* Less aborts and logs instead for M68K

qemu/target-m68k/helper.c

@@ -142,8 +142,9 @@ void HELPER(movec)(CPUM68KState *env, uint32_t reg, uint32_t val)
         break;
     /* TODO: Implement control registers.  */
     default:
-        cpu_abort(CPU(cpu), "Unimplemented control register write 0x%x = 0x%x\n",
-                  reg, val);
+        qemu_log("Unimplemented control register write 0x%x = 0x%x\n",
+                 reg, val);
+        raise_exception(env, EXCP_UNSUPPORTED);
     }
 }