Becoming Hokage infers the meaning that he wants to fight Naruto!!! If you look at the above post you will see the look on the corner of Naruto's eye as well. His goal is always gonna be the same, Kill a certain man. Before Itachi it was Orochimaru; After Itachi, it was Danzo, now it is Madara, and afterwards it will be Naruto…
However, I know why Kishi did not tell us his goal, it is because his goal is what he must have told the Hermit of 6 paths Hagoromo, or at least it will have a lot to do with what he told him before receiving the Yin Powers.
It could be anything really, such as: To restore balance of Power; To become Hokage; To bring his clan back to their original status; To Kill madara; To surpass his comrade Naruto; or even to end the war out there and restore peace amongst the people.
"I have a Dream" (Martin Luther King)... and in my view; dreams are goals that are set that supply the inner energy or drive to shape one's destiny and God guides it.