arch/arm/src: Return ENOTTY when the ioctl command is not recognized.

arch/arm/src/cxd56xx/cxd56_adc.c

@@ -869,7 +869,7 @@ static int cxd56_adc_ioctl(FAR struct file *filep, int cmd,
           else
             {
               aerr("Unrecognized cmd: %d\n", cmd);
-              ret = -EINVAL;
+              ret = -ENOTTY;
             }
         }
         break;

arch/arm/src/stm32/stm32_hrtim.c

@@ -1692,7 +1692,7 @@ static int stm32_hrtim_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
     {
       default:
         {
-          ret = -ENOSYS;
+          ret = -ENOTTY;
           break;
         }
     }