Option 1) Use the Maps API for Java ME with the Blackberry JDK
There is no native Maps API marketed for Blackberry, however the Maps API for Asha is a general Java ME API, whose only dependencies are CLDC1.1 and MIDP2.0, so there is no reason why it shouldn't work with the Blackberry JDE. This article describes the similarities.
There are a series of code examples available which should work out of the box, except for one thing - you'll need to get hold of the jar files which usually reside in
C:/Nokia/Devices/Nokia_Asha_SDK_1_0/plugins/maps api/lib/
which can be obtained from the Nokia Asha SDK.
So all you'll need to do is download the SDK, extract the file maps-core.jar
or any of the other packages you want and access them as external JAR dependencies in the usual manner. See the examples on github for an idea of the capabilities of the library.
Option 2) Use the Map Image API with the low level i/o
Now, if all you need is a single "quick and dirty map", you can make a series of http calls to m.nokia.me
using javax.microedition.io
to get a map on screen. This article explains why using a static map is probably a bad idea, but it would be a simple solution.
Option 3) Create a cross-platform HTML5 app using Cordova or Web Apps
This would be where the Maps API for JavaScript would be useful,