The MemoryManager now works, so we can use the same code as on x86 to
map the framebuffer. Since it uses the MemoryManager, the initialization
of the BootFramebufferConsole has to happen after the MemoryManager is
working.
The BootFramebufferConsole highly depends on using the m_lock spinlock,
therefore setting and changing the cursor state should be done under
that spinlock too to avoid crashing.
All users which relied on the default constructor use a None lock rank
for now. This will make it easier to in the future remove LockRank and
actually annotate the ranks by searching for None.
Instead of seeing a black screen until GraphicsManagement was fully
initialized, this allows us to see the console output much earlier.
So, if the bootloader provided us with a framebuffer, set up a console
as early as possible.
