Speaking literally, Hitler isn't known to have killed anyone after WW1, if he killed anyone during his wartime service.

More practically, prior to the Wannsee Conference in 1942, the Nuremberg Laws codified who was categorized as a Jew, and these provided limits on who could be considered a Jew. However, once the Wannsee Conference protocols took over, who could be considered a Jew included a great deal of subjectivity, in particular those of "mixed blood of the second degree" (those with one Jewish grandparent). According to the minutes of the Wannsee Conference:

2. Treatment of Persons of Mixed Blood of the Second Degree

Persons of mixed blood of the second degree will be treated fundamentally as persons of German blood, with the exception of the following cases, in which the persons of mixed blood of the second degree will be considered as Jews:

a) The person of mixed blood of the second degree was born of a marriage in which both parents are persons of mixed blood.

b) The person of mixed blood of the second degree has a racially especially undesirable appearance that marks him outwardly as a Jew.

c) The person of mixed blood of the second degree has a particularly bad police and political record that shows that he feels and behaves like a Jew.

"Second degree" meant anyone with one Jewish grandparent, with "first-degree" referring to those with two Jewish grandparents. After this point, all bets were off if an authority figure didn't like someone. If one "looked like a Jew" or "acted like a Jew" and couldn't prove that they had no Jewish heritage going back to at least their grandparents, they were at risk of being treated as a Jew. The Nazis clearly were less concerned with technical accuracy than they were with eliminating anything that they saw as problematic as the war went on, and it may have been possible to redefine someone's heritage retroactively if an ancestor could be redefined as a Jew under the new rules.

That said, Germany had experienced decades of relatively friendly relations with Iran, and Hitler maintained and even expanded these, at least until the pro-Allies Mohammed Reza Pahlavi took power from his father. As such, Germany was unlikely to treat an Iranian badly under Hitler's rule, as it could risk a diplomatic incident with a major trade partner.

On the less certain side of this, there are persistent citations online for a "Lenczowski, 1944" suggesting that the Reich Cabinet explicitly exempted Iranians from the racial laws in 1936 on the basis that Iran was peopled by "pure blooded Aryans" and thus equivalent to pure Germans. However, despite quite a bit of searching, I'm unable to attach this to a specific publication. It may be a reference to George Lenczowski, who certainly wrote a great deal about the Middle East and its foreign relations, but there are no 1944 publications listed in WorldCat for him, so without tracking down the individual books and looking for the reference, it's hard to say how accurate this is.