For extremely tight space requirements and specific applications, it is
sometimes desirable to create gPXE images that cannot provide the PXE API
functionality to client programs. Add a configuration header option,
PXE_STACK, that can be removed to remove this stack. Also add PXE_MENU
to control the PXE boot menu, which most uses of gPXE do not need.
Signed-off-by: Marty Connor <mdc@etherboot.org>
EFI provides a copy of the SMBIOS table accessible via the EFI system
table, which we should use instead of manually scanning through the
F000:0000 segment.
The userptr_t is now the fundamental type that gets used for conversions.
For example, virt_to_phys() is implemented in terms of virt_to_user() and
user_to_phys().