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/sbc405.h b/include/configs/sbc405.h
index 187002c..346c847 100644
--- a/include/configs/sbc405.h
+++ b/include/configs/sbc405.h
@@ -36,6 +36,8 @@
 #define CONFIG_4xx		1	/* ...member of PPC4xx family	*/
 #define CONFIG_SBC405		1	/* ...on a WR SBC405 board	*/
 
+#define	CONFIG_SYS_TEXT_BASE	0xFFFC0000
+
 #define CONFIG_BOARD_EARLY_INIT_F 1	/* call board_early_init_f()	*/
 #define CONFIG_MISC_INIT_R	1	/* call misc_init_r()		*/