There is simply no advantage with putting both virtual console devices
and serial TTY devices on the same major number.
Putting them on separate major numbers greatly simplifies the allocation
mechanism on the DeviceMapper code, because it no longer needs to
calculate offsets of minor numbers, and should start from number 0 to
theoretically infinite amount of device nodes.
We don't really need it, and the entire functionality can be organically
intergrated into the VirtualConsole class, to switch between the Virtual
consoles, and manage initialization of all consoles in the global array.
These changes are compatible with clang-format 16 and will be mandatory
when we eventually bump clang-format version. So, since there are no
real downsides, let's commit them now.
Automarks are similar to bookmarks placed by the terminal, allowing the
user to selectively remove a single command and its output from the
terminal scrollback.
This commit implements a single way to add marks: automatically placing
them when the shell becomes interactive.
To make sure the shell behaves correctly after its expected prompt
position changes, the terminal layer forces a resize event to be passed
to the shell on such (possibly) partial clears; this also has the nice
side effect of fixing the disappearing prompt on the preexisting "clear
including history" action: Fixes#4192.
