Note that there is a Spring Data JPA project. JPA is a Java standard for entity persistence, but it needs a persistence provider. I have no numbers, but I would say the leading persistence provider in the Java space is Hibernate.
So Spring Data has decided to make it easier to use the JPA standard and decoupled itself from Hibernate directly and specifically. But Hibernate is still around through the Spring Data JPA abstraction.
Note however that the original Spring Framework does indeed have direct Hibernate support.