Yes, it's ungrammatical to say:

Happiness awaits for you.


The verb await in the sentence 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.