util: split all hostname related calls into hostname-util.c

src/test/test-condition.c

@@ -28,6 +28,7 @@
 #include "ima-util.h"
 #include "apparmor-util.h"
 #include "smack-util.h"
+#include "hostname-util.h"
 
 static void test_condition_test_path(void) {
         Condition *condition;

src/test/test-unit-file.c

@@ -36,6 +36,7 @@
 #include "strv.h"
 #include "fileio.h"
 #include "test-helper.h"
+#include "hostname-util.h"
 
 static int test_unit_file_get_set(void) {
         int r;

src/test/test-unit-name.c

@@ -35,6 +35,7 @@
 #include "macro.h"
 #include "path-util.h"
 #include "test-helper.h"
+#include "hostname-util.h"
 
 static void test_unit_name_is_valid(void) {
         assert_se(unit_name_is_valid("foo.service", UNIT_NAME_ANY));

src/test/test-util.c

@@ -38,6 +38,7 @@
 #include "conf-parser.h"
 #include "virt.h"
 #include "process-util.h"
+#include "hostname-util.h"
 
 static void test_streq_ptr(void) {
         assert_se(streq_ptr(NULL, NULL));