ARM: make sure we cleanup after the bootloader

The "2nd" assert that we always ran into was due to bootloader mappings
still being active after VM init. Turns out we missed a call in the
architecture specific code for cleaning this up.

Many thanks to Ingo for spending the time to figure this out!
ARM: add DTS files required for Beagle-XM target

These were taking from mainline Linux (arch/arm/boot/dts)
HaikuDepot: Make sure to pick up changed package action labels
HaikuDepot: Store package file name in PackageInfo

Also removed misplaced WIP functionality to find deskbar links
HaikuDepot: Implemented "opening" installed packages

Package contents are scanned to find deskbar links. If a package has less
than four links, they will be offered in separate "Open <link name>" buttons
in the package info area. Usually, this results in one button to open the
main application from the package. If the heuristic proves to be not good
enough, this could be improved of course.
HaikuDepot: Extraced LinkView and ScrollableGroupView...

... from PackageInfoView.cpp into their own files in ui_generic.
HaikuDepot: Extracted MessagePackageListener...

... from PackageInfoView into its own files.
HaikuDepot: Beginnings of "featured packages" view

Currently a vertically scrollable container for views which are similar
to the title area in the package info view (and share most code, but it
will diverge later on). Untested and not yet used.
HaikuDepot: Extracted MarkupTextView into its own files
HaikuDepot: Work in progress on featured packages

Not yet visible. But the package list area in the main window has a card
layout now and a second (hidden) page for featured packages. Which packages
are visible there will depend on the prominence value from the web-app
and other parameters later (suggestions based on packages already installed
and user-ratings). At the moment, there is no mechanism for updating the
package list when package info is retrieved asynchronously, even from the
cache. Also, the view should switch to the list when searching and perhaps
in other situations as well, like selecting a category or when no packages
would be featured. And clicking featured packages does not yet select them in
the info area...