networkd-network-gperf.gperf: Add various missing includes

We currently include these transitively but to allow using IWYU to
remove headers later, let's add these as direct includes so the IWYU
changes don't break compilation.

src/network/networkd-network-gperf.gperf

@@ -4,12 +4,14 @@ _Pragma("GCC diagnostic ignored \"-Wimplicit-fallthrough\"")
 #if __GNUC__ >= 15
 _Pragma("GCC diagnostic ignored \"-Wzero-as-null-pointer-constant\"")
 #endif
+#include <linux/can/netlink.h>
 #include <netinet/icmp6.h>
 #include <stddef.h>
 
 #include "conf-parser.h"
 #include "in-addr-prefix-util.h"
 #include "net-condition.h"
+#include "netif-sriov.h"
 #include "networkd-address-generation.h"
 #include "networkd-address-label.h"
 #include "networkd-address.h"
@@ -38,6 +40,7 @@ _Pragma("GCC diagnostic ignored \"-Wzero-as-null-pointer-constant\"")
 #include "networkd-routing-policy-rule.h"
 #include "networkd-sriov.h"
 #include "qdisc.h"
+#include "socket-util.h"
 #include "tclass.h"
 #include "vlan-util.h"