sd-bus: make sure bus_map_all_properties() handle booleans right

sd-bus generally exposes bools as "int" instead of "bool" in the public API.
This is relevant when unmarshaling booleans, as the relevant functions expect
an int* pointer and no bool* pointer. Since sizeof(bool) is not necessarily the
same as sizeof(int) this is problematic and might result in memory corruption.

Let's fix this, and make sure bus_map_all_properties() handles booleans as
ints, as the rest of sd-bus, and make all users of it expect the right thing.

src/shared/bus-util.c

@@ -1048,7 +1048,7 @@ static int map_basic(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_
 
         case SD_BUS_TYPE_BOOLEAN: {
                 unsigned b;
-                bool *p = userdata;
+                int *p = userdata;
 
                 r = sd_bus_message_read_basic(m, type, &b);
                 if (r < 0)