docs: ranoops.rst: fix location of ramoops.txt

The location of the dt bindings file is wrong: it was probably
badly renamed by some script.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/admin-guide/ramoops.rst

@@ -61,7 +61,7 @@ Setting the ramoops parameters can be done in several different manners:
 	mem=128M ramoops.mem_address=0x8000000 ramoops.ecc=1
 
  B. Use Device Tree bindings, as described in
- ``Documentation/device-tree/bindings/reserved-memory/admin-guide/ramoops.rst``.
+ ``Documentation/devicetree/bindings/reserved-memory/ramoops.txt``.
  For example::
 
 	reserved-memory {