Fix post_code in 16bit entry

Relocate early post_code() so it gets executed and does not corrupt
BIST at %eax.

Change-Id: Ieeebcb23f7c327e501b410eaa60d1e49110ee988
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/439
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/arch/x86/init/prologue.inc

@@ -23,7 +23,3 @@
 .section ".rom.data", "a", @progbits
 .section ".rom.text", "ax", @progbits
 
-/* This is the entry code. The code in the .reset section jumps here. */
-
-	post_code(POST_RESET_VECTOR_CORRECT)
-

src/cpu/x86/16bit/entry16.inc

@@ -36,6 +36,8 @@ _start:
 	/* Save the BIST result */
 	movl	%eax, %ebp
 
+	post_code(POST_RESET_VECTOR_CORRECT)
+
 /* thanks to kmliu@sis.tw.com for this TBL fix ... */
 /**/
 /* IMMEDIATELY invalidate the translation lookaside buffer before executing*/