spl: Allow tiny printf() to be controlled in SPL and TPL

At present there is only one control for this and it is used for both SPL
and TPL. But SPL might have a lot more space than TPL so the extra cost of
a full printf() might be acceptable.

Split the option into two, providing separate SPL and TPL controls. The
TPL setting defaults to the same as SPL.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/common/spl/Kconfig b/common/spl/Kconfig
index 62b93c1..048b85b 100644
--- a/common/spl/Kconfig
+++ b/common/spl/Kconfig
@@ -963,7 +963,7 @@
 	  for displaying messages while SPL is running. It also brings in
 	  printf() and panic() functions. This should normally be enabled
 	  unless there are space reasons not to. Even then, consider
-	  enabling USE_TINY_PRINTF which is a small printf() version.
+	  enabling SPL_USE_TINY_PRINTF which is a small printf() version.
 
 config SPL_SPI_FLASH_SUPPORT
 	bool "Support SPI flash drivers"