Allocate ever an extra page behind the commandline pointer. If it turns out
that this page is unused, because commandline was short enough, unmap the
memory and put the virtual and physical regions back to the allocator.
Fix#664
We don't can use map_local_one_to_one for boot modules because it happens
that boot modules can be at addresses above physical 3G boundary for x86_32.
Defer the mapping of modules until the point where the core allocators
are set up properly and then remap the physical pages to virtual addresses
below 3G.
If the I/O ports are non default (3f8), we had to specify manually the correct
I/O ports. With this commit the BDA is read and the I/O port of the first
serial interface (COM) is taken. If no serial interface is available no device
configuration will be undertaken.
