PPC maintainers

I'm retiring from IBM, and Geoff hasn't been active for a very long
time.

	* MAINTAINERS (ppc): Remove myself and Geoff Keating.  Add
	Geoff to past maintainers.

binutils/MAINTAINERS

@@ -125,8 +125,6 @@ responsibility among the other maintainers.
   OR1K		   Christian Svensson <blue@cmd.nu>
   OR1K		   Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
   OR1K		   Stafford Horne <shorne@gmail.com>
-  PPC		   Geoff Keating <geoffk@geoffk.org>
-  PPC		   Alan Modra <amodra@gmail.com>
   PPC		   Peter Bergner <bergner@vnet.ibm.com>
   PPC vector ext   Aldy Hernandez <aldyh@redhat.com>
   RISC-V	   Palmer Dabbelt <palmer@dabbelt.com>
@@ -167,6 +165,7 @@ goes with them.
   Paul Brook
   Eric Christopher
   Jason Eckhardt
+  Geoff Keating
   Mark Kettenis
   Mei Ligang
   Arnold Metselaar