netdev-genl: Support setting per-NAPI config values

Add support to set per-NAPI defer_hard_irqs and gro_flush_timeout.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241011184527.16393-7-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/netlink/specs/netdev.yaml

@@ -693,6 +693,17 @@ operations:
         reply:
           attributes:
             - id
+    -
+      name: napi-set
+      doc: Set configurable NAPI instance settings.
+      attribute-set: napi
+      flags: [ admin-perm ]
+      do:
+        request:
+          attributes:
+            - id
+            - defer-hard-irqs
+            - gro-flush-timeout
 
 kernel-family:
   headers: [ "linux/list.h"]