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/ep8260.h b/include/configs/ep8260.h
index 482b348..ab646ae 100644
--- a/include/configs/ep8260.h
+++ b/include/configs/ep8260.h
@@ -48,6 +48,8 @@
 #define CONFIG_SYS_EP8260_H2	1
 /* #undef CONFIG_SYS_EP8260_H2  */
 
+#define	CONFIG_SYS_TEXT_BASE	0xFFF00000
+
 #define CONFIG_CPM2		1	/* Has a CPM2 */
 
 /* What is the oscillator's (UX2) frequency in Hz? */