devlink: Move devlink fmsg and health diagnose to health file

Devlink fmsg (formatted message) is used by devlink health diagnose,
dump and drivers which support these devlink health callbacks.
Therefore, move devlink fmsg helpers and related code to file health.c.
Move devlink health diagnose to file health.c. No functional change in
this patch.
Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/devlink/devl_internal.h

@@ -240,7 +240,11 @@ devlink_nl_health_reporter_fill(struct sk_buff *msg,
 int devlink_health_do_dump(struct devlink_health_reporter *reporter,
 			   void *priv_ctx,
 			   struct netlink_ext_ack *extack);
+int devlink_fmsg_dumpit(struct devlink_fmsg *fmsg, struct sk_buff *skb,
+			struct netlink_callback *cb,
+			enum devlink_command cmd);
 
+struct devlink_fmsg *devlink_fmsg_alloc(void);
 void devlink_fmsg_free(struct devlink_fmsg *fmsg);
 
 /* Line cards */
@@ -272,3 +276,5 @@ int devlink_nl_cmd_health_reporter_set_doit(struct sk_buff *skb,
 					    struct genl_info *info);
 int devlink_nl_cmd_health_reporter_recover_doit(struct sk_buff *skb,
 						struct genl_info *info);
+int devlink_nl_cmd_health_reporter_diagnose_doit(struct sk_buff *skb,
+						 struct genl_info *info);