Reverted AV610 USB IDs and removed AV_INT_STATUS

Previously I had changed the USB ID of this scanner from 0x0a18 back to
0x0a19, believing a previous commit to have been in error since it went
unmentioned in the commit log and duplicated the AV600U Plus scanner's USB
IDs.  Rolf Würdemann reported that his AV610 scanner used the 0x0a18 ID and
that it wasn't compatible with the AV_INT_STATUS flag.  This commit reverts
my USB ID changes and removes the AV_INT_STATUS flag for the AV610.

However, because this scanner shares its USB ID with the AV600U Plus, it's
possible that the AV600U Plus may require that the AV_INT_STATUS flag be set
in order to function, and thus will break with this change.  The code, as
it's written, isn't designed to deal well with the possibility of shared USB
IDs, so I'll wait to see if this actually becomes a problem before embarking
on the lengthy challenge of getting that to work.

backend/avision.c

@@ -331,15 +331,16 @@ static Avision_HWEntry Avision_Device_List [] =
     /* status="untested" */
     
     { NULL, "AV610",
-      0x0638, 0x0a19,
+      0x0638, 0x0a18,
       "Avision", "AV610",
-      AV_GRAY_CALIB_BLUE | AV_ACCEL_TABLE | AV_NO_64BYTE_ALIGN | AV_INT_STATUS | AV_INT_BUTTON,0},
+      AV_GRAY_CALIB_BLUE | AV_ACCEL_TABLE | AV_NO_64BYTE_ALIGN | AV_INT_BUTTON, 0},
     /* status="good" */
 
     { NULL, NULL,
       0x0638, 0x0a18,
       "Avision", "AV600U Plus",
-      AV_GRAY_CALIB_BLUE | AV_ACCEL_TABLE | AV_NO_64BYTE_ALIGN | AV_INT_STATUS | AV_INT_BUTTON,0},
+      /* If this unit requires the AV_INT_STATUS flag, then we'll need to alter the code to deal with two different devices with the same USB id (AV610 above) */
+      AV_GRAY_CALIB_BLUE | AV_ACCEL_TABLE | AV_NO_64BYTE_ALIGN | /* AV_INT_STATUS | */ AV_INT_BUTTON,0},
     /* status="good" */
 
     { NULL, NULL,

doc/descriptions/avision.desc

@@ -163,7 +163,7 @@
 
 :model "AV610"
 :interface "USB"
-:usbid "0x0638" "0x0a19"
+:usbid "0x0638" "0x0a18"
 :status :good
 
 :model "AV600U Plus"