netlink: specs: fix up truthy values

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>

Documentation/netlink/specs/devlink.yaml

@@ -744,7 +744,7 @@ attribute-sets:
         name: flash-update-overwrite-mask
         type: bitfield32
         enum: flash-overwrite
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: reload-action
         type: u8
@@ -753,12 +753,12 @@ attribute-sets:
         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
@@ -917,7 +917,7 @@ attribute-sets:
         name: caps
         type: bitfield32
         enum: port-fn-attr-cap
-        enum-as-flags: True
+        enum-as-flags: true
 
   -
     name: dl-dpipe-tables

Documentation/netlink/specs/nl80211.yaml

@@ -680,7 +680,7 @@ attribute-sets:
         name: feature-flags
         type: u32
         enum: feature-flags
-        enum-as-flags: True
+        enum-as-flags: true
       -
         name: probe-resp-offload
         type: u32