hwmon: (max6620) Update broken Datasheet URL in driver documentation

The URL for the MAX6620 datasheet has changed. Update it to reflect the
current location.

Signed-off-by: Okan Akyuz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[groeck: Updated subject and patch description]
Signed-off-by: Guenter Roeck <[email protected]>

Author: okanakyuz

Documentation/hwmon/max6620.rst

@@ -11,7 +11,7 @@ Supported chips:
 
     Addresses scanned: none
 
-    Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6620.pdf
+    Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max6620.pdf
 
 Authors:
     - L\. Grunenberg <[email protected]>