efi: remove old SetVirtualAddressMap() arrangement

efi: remove old SetVirtualAddressMap() arrangement

Remove unused (#ifdef-ed out) code. Reviving it in its current shape
won't fly because:
 - SetVirtualAddressMap() needs to be called with 1:1 mapping, which
   isn't the case at this time
 - it uses directmap, which may go away soon
 - it uses directmap, which is mapped with NX, breaking EfiRuntimeServicesCode

No functional change.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>