Yes, it's ungrammatical to say:
Happiness awaits for you.
The verb await is a transitive verb that is followed by a direct object; you don't use the preposition "for". So it's correct to say:
Happiness awaits you.
Instead of the await, you can use the intransitive verb wait, usually as (be) -ing form, followed by the preposition "for" as follows:
Happainess waits for you/Hapiness is waiting for you.