Move lib_$ARCH directories to arch/$ARCH/lib

Also move lib_$ARCH/config.mk to arch/$ARCH/config.mk

This change is intended to clean up the top-level directory structure
and more closely mimic Linux's directory organization.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/board/freescale/m52277evb/u-boot.spa b/board/freescale/m52277evb/u-boot.spa
index 7ae70d4..23d5710 100644
--- a/board/freescale/m52277evb/u-boot.spa
+++ b/board/freescale/m52277evb/u-boot.spa
@@ -57,7 +57,7 @@
 
     cpu/mcf5227x/start.o	(.text)
     cpu/mcf5227x/libmcf5227x.a	(.text)
-    lib_m68k/libm68k.a		(.text)
+    arch/m68k/lib/libm68k.a		(.text)
     lib_generic/libgeneric.a	(.text)
     common/cmd_mem.o		(.text)
     common/main.o		(.text)