JOEL4: more debugging info in page fault handler

Fixed up the names for x86 paging flags. Added a new debugging function
that can print out the non-zero values in the page directory.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: setting up system calls to use SYSENTER

We need the ability to pass more than one parameter, and the method
specified in the X.2 document is not compatible with the SYSENTER
method. This does not solve the problem, but is a step in the right
direction.

Signed-off-by: Joel Nider <joel@nider.org>