I think that either ハニーフ or ハニフ is probably what you want.
As has been mentioned in the comments, both seem to be used by people with the same name. I think the best way to choose between the two is to use the pronunciation/intonation in your native language as a guide:
if you pronounce your name as Hanif (i.e. the stress on the first syllable / short i), you might want to go for ハニフ
if you pronounce it Hanif (i.e. stress on the second syllable / long i), you might want to go for ハニーフ.
(The reason is that the natural pitch accent will be ハニフ【HLL】 and ハニーフ【LHLL】 and one of those would be a better match for the intonation in your language.)