log: Plumb logging into the init sequence

Set up logging both before and after relocation.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index 77755db..73e036d 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -146,5 +146,6 @@
 #define GD_FLG_RECORD		0x01000	/* Record console		   */
 #define GD_FLG_ENV_DEFAULT	0x02000 /* Default variable flag	   */
 #define GD_FLG_SPL_EARLY_INIT	0x04000 /* Early SPL init is done	   */
+#define GD_FLG_LOG_READY	0x08000 /* Log system is ready for use	   */
 
 #endif /* __ASM_GENERIC_GBL_DATA_H */