doc: netlink: Don't 'sanitize' op docstrings in generated .rst

The doc strings for do/dump ops are emitted as toplevel .rst constructs
so they can be multi-line. Pass multi-line text straight through to the
.rst to retain any simple formatting from the .yaml

This fixes e.g. list formatting for the pin-get docs in dpll.yaml:

https://docs.kernel.org/6.9/networking/netlink_spec/dpll.html#pin-getSigned-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240528140652.9445-3-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/netlink/specs/dpll.yaml

@@ -479,6 +479,7 @@ operations:
       name: pin-get
       doc: |
         Get list of pins and its attributes.
+
         - dump request without any attributes given - list all the pins in the
           system
         - dump request with target dpll - list all the pins registered with

tools/net/ynl/ynl-gen-rst.py

@@ -178,7 +178,7 @@ def parse_operations(operations: List[Dict[str, Any]], namespace: str) -> str:
 
     for operation in operations:
         lines.append(rst_section(namespace, 'operation', operation["name"]))
-        lines.append(rst_paragraph(sanitize(operation["doc"])) + "\n")
+        lines.append(rst_paragraph(operation["doc"]) + "\n")
 
         for key in operation.keys():
             if key in preprocessed: