Avoid unnecessary call to post_word_load();

make logbuf compile without POST

common/cmd_log.c

@@ -93,7 +93,7 @@ void logbuff_init_ptrs (void)
  	}
 #else
 	/* No post routines, so we do our own checking                    */
- 	if (post_word_load () != LOGBUFF_MAGIC) {
+ 	if (post_word != LOGBUFF_MAGIC) {
  		logged_chars = log_size = log_start = 0;
 		post_word_store (LOGBUFF_MAGIC);
 		*ext_tag = LOGBUFF_MAGIC;

include/asm-ppc/global_data.h

@@ -70,7 +70,7 @@ typedef	struct	global_data {
 #if defined(CONFIG_LCD) || defined(CONFIG_VIDEO)
 	unsigned long	fb_base;	/* Base address of framebuffer memory	*/
 #endif
-#ifdef CONFIG_POST
+#if defined(CONFIG_POST) || defined(CONFIG_LOGBUFFER)
 	unsigned long	post_log_word;  /* Record POST activities */
 	unsigned long	post_init_f_time;  /* When post_init_f started */
 #endif