Clean up all truthy value warnings reported by yamllint in the
netlink specs:
    warning  truthy value should be one of [false, true]  (truthy)
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> # mptcp_pm.yaml
Link: https://patch.msgid.link/20250610125944.85265-5-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
         name: flash-update-overwrite-mask
         type: bitfield32
         enum: flash-overwrite
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: reload-action
         type: u8
         name: reload-actions-performed
         type: bitfield32
         enum: reload-action
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: reload-limits
         type: bitfield32
         enum: reload-action
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: dev-stats
         type: nest
         name: caps
         type: bitfield32
         enum: port-fn-attr-cap
-        enum-as-flags: True
+        enum-as-flags: true
 
   -
     name: dl-dpipe-tables
 
         name: feature-flags
         type: u32
         enum: feature-flags
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: probe-resp-offload
         type: u32