10132 smatch fixes for MDB
Reviewed by: Andy Fiddaman <andy@omniosce.org>

@@ -1518,13 +1518,13 @@
                 return ("[ shmem ]");
         if (map->map_flags & MDB_TGT_MAP_STACK)
                 return ("[ stack ]");
         if (map->map_flags & MDB_TGT_MAP_ANON)
                 return ("[ anon ]");
-        if (map->map_name != NULL)
-                return (map->map_name);
+        if (map->map_name[0] == '\0')
         return ("[ unknown ]");
+        return (map->map_name);
 }
 
 /*ARGSUSED*/
 static int
 print_map(void *ignored, const mdb_map_t *map, const char *name)

@@ -2341,11 +2341,11 @@
 {
         uint64_t cnt = 10;
         const char *c;
         mdb_pipe_t p;
 
-        if (!flags & DCMD_PIPE)
+        if (!(flags & DCMD_PIPE))
                 return (DCMD_USAGE);
 
         if (argc == 1 || argc == 2) {
                 const char *num;