powerpc/configs: Make pseries_le an alias for ppc64le_guest

Rather than trying to keep multiple configs up to date, make
pseries_le_defconfig an alias for ppc64le_guest_defconfig.

ppc64le_guest_defconfig should work in all cases that
pseries_le_defconfig currently does, but if not we can update it.

Move pseries_le_defconfig down in the Makefile, so it appears after
ppc64le_guest_defconfig in the help output.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230414132415.821564-31-mpe@ellerman.id.au

arch/powerpc/Makefile

@@ -248,10 +248,6 @@ bootwrapper_install:
 
 include $(srctree)/scripts/Makefile.defconf
 
-generated_configs += pseries_le_defconfig
-pseries_le_defconfig:
-	$(call merge_into_defconfig,pseries_defconfig,le)
-
 generated_configs += ppc64le_defconfig
 ppc64le_defconfig:
 	$(call merge_into_defconfig,ppc64_defconfig,le)
@@ -264,6 +260,9 @@ generated_configs += ppc64_guest_defconfig
 ppc64_guest_defconfig:
 	$(call merge_into_defconfig,ppc64_defconfig,be guest kvm_guest)
 
+generated_configs += pseries_le_defconfig
+pseries_le_defconfig: ppc64le_guest_defconfig
+
 generated_configs += powernv_be_defconfig
 powernv_be_defconfig:
 	$(call merge_into_defconfig,powernv_defconfig,be)