dhcp: introduce sd_dhcp_duid and move relevant functions to sd_dhcp_duid.[ch]

src/network/networkd-dhcp-common.c

@@ -5,7 +5,6 @@
 
 #include "bus-error.h"
 #include "bus-locator.h"
-#include "dhcp-identifier.h"
 #include "dhcp-option.h"
 #include "dhcp6-internal.h"
 #include "escape.h"

src/network/networkd-dhcp-common.h

@@ -4,7 +4,7 @@
 #include <netinet/in.h>
 
 #include "conf-parser.h"
-#include "dhcp-identifier.h"
+#include "dhcp-duid-internal.h"
 #include "in-addr-util.h"
 #include "set.h"
 #include "time-util.h"

src/network/networkd-link.c

@@ -17,7 +17,6 @@
 #include "bus-util.h"
 #include "device-private.h"
 #include "device-util.h"
-#include "dhcp-identifier.h"
 #include "dhcp-lease-internal.h"
 #include "env-file.h"
 #include "ethtool-util.h"

src/network/networkd-manager.h

@@ -8,7 +8,7 @@
 #include "sd-netlink.h"
 #include "sd-resolve.h"
 
-#include "dhcp-identifier.h"
+#include "dhcp-duid-internal.h"
 #include "firewall-util.h"
 #include "hashmap.h"
 #include "networkd-link.h"