Inform make which cmds are dash builtins.

Change-Id: I1aa9d6bc6578c3ebd4247604cf0004ae0edbaf2d
diff --git a/job.c b/job.c
index c985a72..6d5a5cb 100644
--- a/job.c
+++ b/job.c
@@ -2755,6 +2755,13 @@
 #elif defined(__riscos__)
   static const char *sh_chars = "";
   static const char *sh_cmds[] = { 0 };
+#elif defined(__Fuchsia__)
+  static const char *sh_chars = "#;\"*?[]&|<>(){}$`^~!";
+  static const char *sh_cmds[] =
+    { ".", ":", "break", "case", "cd", "continue", "echo", "eval", "exec",
+      "exit", "export", "for", "if", "ls", "read", "readonly", "set", "shift",
+      "switch", "test", "times", "trap", "umask", "unset", "wait", "while",
+      0 };
 #else  /* must be UNIX-ish */
   static const char *sh_chars = "#;\"*?[]&|<>(){}$`^~!";
   static const char *sh_cmds[] =