bus: rename message "serial" to "cookie"

Even if the lower-leveld dbus1 protocol calls it "serial", let's expose
the word "cookie" for this instead, as this is what kdbus uses and since
it doesn't imply monotonicity the same way "serial" does.

src/shared/capability.c

@@ -137,7 +137,7 @@ int capability_bounding_set_drop(uint64_t drop, bool right_now) {
                                 r = -errno;
                                 goto finish;
                         }
-                        v = i;
+                        v = (cap_value_t) i;
 
                         /* Also drop it from the inheritable set, so
                          * that anything we exec() loses the

src/shared/install.c

@@ -1020,9 +1020,9 @@ static int unit_file_load(
                 return r;
 
         return
-                strv_length(info->aliases) +
-                strv_length(info->wanted_by) +
-                strv_length(info->required_by);
+                (int) strv_length(info->aliases) +
+                (int) strv_length(info->wanted_by) +
+                (int) strv_length(info->required_by);
 }
 
 static int unit_file_search(
@@ -1132,9 +1132,9 @@ static int unit_file_can_install(
 
         if (r >= 0)
                 r =
-                        strv_length(i->aliases) +
-                        strv_length(i->wanted_by) +
-                        strv_length(i->required_by);
+                        (int) strv_length(i->aliases) +
+                        (int) strv_length(i->wanted_by) +
+                        (int) strv_length(i->required_by);
 
         return r;
 }

src/shared/util.h

@@ -712,7 +712,7 @@ static inline void _reset_umask_(struct _umask_struct_ *s) {
              _saved_umask_.quit = true)
 
 static inline unsigned u64log2(uint64_t n) {
-        return (n > 1) ? __builtin_clzll(n) ^ 63U : 0;
+        return (n > 1) ? (unsigned) __builtin_clzll(n) ^ 63U : 0;
 }
 
 static inline bool logind_running(void) {