Documentation/ABI: Fix documentation inconsistency for mlxreg-io sysfs interfaces

Fix attribute name from "jtag_enable", which described twice to
"cpld3_version", which is expected to be instead of second appearance
of "jtag_enable".

Fixes: 2752e344 ("Documentation/ABI: Add new attribute for mlxreg-io sysfs interfaces")
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Documentation/ABI/stable/sysfs-driver-mlxreg-io

@@ -29,13 +29,13 @@ Description:	This file shows the system fans direction:
 
 		The files are read only.
 
-What:		/sys/devices/platform/mlxplat/mlxreg-io/hwmon/hwmon*/jtag_enable
+What:		/sys/devices/platform/mlxplat/mlxreg-io/hwmon/hwmon*/cpld3_version
 
 Date:		November 2018
 KernelVersion:	5.0
 Contact:	Vadim Pasternak <vadimpmellanox.com>
 Description:	These files show with which CPLD versions have been burned
-		on LED board.
+		on LED or Gearbox board.
 
 		The files are read only.