Does The Autobiography of Malcolm X have any reference to white guilt, as opposed to the belief that all white men subscribe to the American system perceived to hold black men down?
As we learn in the Autobiography of Malcolm X, though Malcolm X started out with very strong black separatist sentiments due to the influence of Elijah Muhammad, Malcolm X had a very drastic change of heart once he made the pilgrimage to Mecca.
In chapter 17, titled "Mecca," we learn that on his journey to Mecca, Malcolm was struck by the sight of so many different races all bonding together in brotherhood. His perspective is best noted in the observation he makes in the plane on the way to Jedda: "Packed in the plane were white, black, brown, red, and yellow people, blue eyes and blond hair, and my kinky red hair--all together, brothers!" (p. 203) But what influenced him most on this journey was meeting Dr. Abd-Al-Rahman Azzam.
Prior to leaving America, Malcolm had to go to Dr. Manmoud Youssef Shawarbi to request a signed letter of approval to make the pilgrimage to Mecca. While in Dr. Shawarbi's's office, Malcolm is given a copy of The Eternal Message of Muhammad that Dr. Shawarbi says was sent specifically to Malcolm by the book's author Dr. Azzam. Later, while in Jedda, Malcolm gets the opportunity to actually meet Dr. Azzam, a white man. Most significantly, Malcolm is struck by Dr. Azzam's hospitality, hospitality Malcolm had never experienced before, not by any race. Dr. Azzam actually gave Malcolm the use of his own hotel suite while Dr. Azzam stayed at his son's home. Most importantly, when Malcolm got to meet Dr. Azzam face to face, Malcolm was struck by the fact that he was treated as family.
Malcolm's experience with Dr. Azzam changed Malcolm's entire perspective on white men, for he came to understand that the term "white man" wasn't used to reflect a race so much as it was used to reflect "specific attitudes and actions toward the black man, and toward all other non-white men" (p. 209). Yet, in Mecca, he learned about "color-blindness" and how to treat all as brothers (p. 212). Hence, it is at this point he decides separatism is not the answer to solving racial problems in America; instead brotherhood is the answer.
Hence, we can certainly interpret his references to Dr. Azzam as a reference to what you are calling "white guilt," which as you say, would be the belief that white men did not have to act in the ways prescribed by white American society. As Malcolm phrased it himself, "We were truly all the same [brothers] because their belief in one God had removed the 'white' from their minds, the 'white' from their behavior, and the 'white' from their attitude" (p. 213).