libxl: build, check and pass vNUMA info to Xen for HVM guest

libxl: build, check and pass vNUMA info to Xen for HVM guest

Transform user supplied vNUMA configuration into libxl internal
representations then libxc representations. Check validity along the
line.

Libxc has more involvement in building vmemranges in HVM case compared
to PV case. The building of vmemranges is placed after xc_hvm_build
returns, because it relies on memory hole information provided by
xc_hvm_build.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Elena Ufimtseva <ufimtseva@gmail.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>