MAINTAINERS: Adjust file list for PPC pseries machine

The fdt.{c.h} files provide a helper routine used by the pseries and
pnv machines. Attached it to the list of the larger one: pseries.

Protected Execution Facility (PEF) is the confidential guest support
for PPC pseries machines.

Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

MAINTAINERS

@@ -1463,6 +1463,10 @@ F: hw/*/spapr*
 F: include/hw/*/spapr*
 F: hw/*/xics*
 F: include/hw/*/xics*
+F: include/hw/ppc/fdt.h
+F: hw/ppc/fdt.c
+F: include/hw/ppc/pef.h
+F: hw/ppc/pef.c
 F: pc-bios/slof.bin
 F: docs/system/ppc/pseries.rst
 F: docs/specs/ppc-spapr-*