Hi,
VisualGDB takes the Android platform list from the <VisualGDB directory>\Rules\Android\AndroidPlatforms.xml file. If the platform you are using it not listed there, please consider editing the file, or using the latest VisualGDB 5.4 Preview 10 that includes the definitions for the latest platforms.
VisualGDB provides 2 different settings for the Android platforms: SDK platform and NDK platform (that might be different for older SDK/NDK versions). The SDK platform setting corresponds to the project.properties file used by Ant, while the NDK platform corresponds to the Application.mk file.