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/MVBC_P.h b/include/configs/MVBC_P.h
index 05603be..cd86766 100644
--- a/include/configs/MVBC_P.h
+++ b/include/configs/MVBC_P.h
@@ -32,6 +32,10 @@
 #define CONFIG_MPC5xxx	1
 #define CONFIG_MPC5200 	1
 
+#ifndef CONFIG_SYS_TEXT_BASE
+#define CONFIG_SYS_TEXT_BASE	0xFF800000
+#endif
+
 #define CONFIG_SYS_MPC5XXX_CLKIN	33000000
 
 #define BOOTFLAG_COLD		0x01