[POWERPC] Add zImage.iseries to arch/powerpc/boot/.gitignore

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/boot/.gitignore

@@ -27,6 +27,7 @@ zImage.chrp
 zImage.coff
 zImage.coff.lds
 zImage.ep*
+zImage.iseries
 zImage.*lds
 zImage.miboot
 zImage.pmac