docs: hwmon: (ltc2945) update datasheet link

Old one isn't working anymore. Update to the latest datasheet link.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201005131226.1774081-1-alexandru.ardelean@analog.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/ltc2945.rst

@@ -11,7 +11,7 @@ Supported chips:
 
     Datasheet:
 
-	http://cds.linear.com/docs/en/datasheet/2945fa.pdf
+	https://www.analog.com/media/en/technical-documentation/data-sheets/2945fb.pdf
 
 Author: Guenter Roeck <linux@roeck-us.net>