Add selfboot to the romstage

Now that bounce buffers are gone, and we can elide the selfload checking
code at build time, it is safe to add selfboot to the romstage.

Make it so.

This required a few other tweaks to rules.h and selfboot.c
to make it buildon ARM.

Change-Id: Ib6540921ad7cd7d58bfeab881d3978325b303cc2
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/29338
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Hug <philipp@hug.cx>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/lib/Makefile.inc

@@ -92,6 +92,7 @@ romstage-y += region_file.c
 ramstage-y += romstage_handoff.c
 romstage-y += romstage_handoff.c
 romstage-y += romstage_stack.c
+romstage-y += selfboot.c
 ramstage-y += romstage_stack.c
 romstage-y += stack.c
 ramstage-y += rtc.c

src/lib/selfboot.c

@@ -18,7 +18,6 @@
 #include <commonlib/compression.h>
 #include <commonlib/endian.h>
 #include <console/console.h>
-#include <cpu/cpu.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>