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/PMC440.h b/include/configs/PMC440.h
index 4d3c022..66e2692 100644
--- a/include/configs/PMC440.h
+++ b/include/configs/PMC440.h
@@ -39,6 +39,10 @@
 #define CONFIG_440		1	/* ... PPC440 family    */
 #define CONFIG_4xx		1	/* ... PPC4xx family    */
 
+#ifndef CONFIG_SYS_TEXT_BASE
+#define CONFIG_SYS_TEXT_BASE	0xFFF90000
+#endif
+
 #define CONFIG_SYS_CLK_FREQ	33333400
 
 #if 0 /* temporary disabled because OS/9 does not like dcache on startup */