Makefile: move all Power Architecture boards into boards.cfg

Clean up Makefile, and drop a lot of the config.mk files on the way.

We now also automatically pick all boards that are listed in
boards.cfg (and with all configurations), so we can drop the redundant
entries from MAKEALL to avoid building these twice.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/include/configs/MIP405.h b/include/configs/MIP405.h
index bfff750..a097639 100644
--- a/include/configs/MIP405.h
+++ b/include/configs/MIP405.h
@@ -35,6 +35,9 @@
 #define CONFIG_405GP		1	/* This is a PPC405 CPU		*/
 #define CONFIG_4xx		1	/* ...member of PPC4xx family	*/
 #define CONFIG_MIP405		1	/* ...on a MIP405 board		*/
+
+#define	CONFIG_SYS_TEXT_BASE	0xFFF80000
+
 /***********************************************************
  * Note that it may also be a MIP405T board which is a subset of the
  * MIP405