Since the kernel needs more breathing space in terms of VM, and there are
no things anymore that directly depend on it having a certain value,
I've dropped the kernel VA start address to give it twice more space.

This means that:

	* to compile a new kernel, you MUST do a new config of your kernel,
	  since the KVA start address is contained within the Makefile
	* for libkvm-related applications, it is best that you do
	  a 'make includes' in /usr/src/sys, and recompile libkvm, plus
	  also relink the static ones (like ps(1)).

- Frank