Fix some bugs in dumpsys meminfo attribution

ART image files can end with either .art or .art] depending on where
they are loaded from, add handling for this.

Also fix subheap attribution to HEAP_ART_BOOT and HEAP_ART_APP for
the app image case.

Test: adb shell dumpsys meminfo `pid system_server`
Bug: 134509632

Change-Id: I98882466d7c2f31179b095b803af67d21c17306c