core: pahole optimization of struct Unit

We had a lone 'bool job_running_timeout_set:1', which generated a hole. Let's
move things around a bit. The structure is a tiny bit smaller and has less
holes:
        /* size: 1192, cachelines: 19, members: 149 */
        /* sum members: 1175, holes: 3, sum holes: 11 */
        /* sum bitfield members: 27 bits, bit holes: 1, sum bit holes: 7 bits */
        /* bit_padding: 14 bits */
        /* last cacheline: 40 bytes */

        /* size: 1184, cachelines: 19, members: 149 */
        /* sum members: 1175, holes: 1, sum holes: 4 */
        /* sum bitfield members: 27 bits (3 bytes) */
        /* bit_padding: 13 bits */
        /* last cacheline: 32 bytes */

src/core/unit.h

@@ -120,9 +120,6 @@ typedef struct Unit {
         UnitLoadState load_state;
         Unit *merged_into;
 
-        FreezerState freezer_state;
-        sd_bus_message *pending_freezer_message;
-
         char *id;   /* The one special name that we use for identification */
         char *instance;
 
@@ -150,6 +147,16 @@ typedef struct Unit {
         /* If this is a transient unit we are currently writing, this is where we are writing it to */
         FILE *transient_file;
 
+        /* Freezer state */
+        sd_bus_message *pending_freezer_message;
+        FreezerState freezer_state;
+
+        /* Job timeout and action to take */
+        EmergencyAction job_timeout_action;
+        usec_t job_timeout;
+        usec_t job_running_timeout;
+        char *job_timeout_reboot_arg;
+
         /* If there is something to do with this unit, then this is the installed job for it */
         Job *job;
 
@@ -164,13 +171,6 @@ typedef struct Unit {
         sd_bus_track *bus_track;
         char **deserialized_refs;
 
-        /* Job timeout and action to take */
-        usec_t job_timeout;
-        usec_t job_running_timeout;
-        bool job_running_timeout_set:1;
-        EmergencyAction job_timeout_action;
-        char *job_timeout_reboot_arg;
-
         /* References to this */
         LIST_HEAD(UnitRef, refs_by_target);
 
@@ -359,6 +359,8 @@ typedef struct Unit {
 
         bool sent_dbus_new_signal:1;
 
+        bool job_running_timeout_set:1;
+
         bool in_audit:1;
         bool on_console:1;