spl: Use CONFIG_SPL... instead of CONFIG_..._SPL_...

We like to put the SPL first so it is clear that it relates to SPL. Rename
various malloc-related options which have crept in, to stick to this
convention.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Martyn Welch <martyn.welch@collabora.com>
Reviewed-by: Svyatoslav Ryhel <clamor95@gmail.com>
diff --git a/include/system-constants.h b/include/system-constants.h
index 0d6b71b..f0a191b 100644
--- a/include/system-constants.h
+++ b/include/system-constants.h
@@ -22,10 +22,10 @@
 /*
  * Typically, we have the SPL malloc pool at the end of the BSS area.
  */
-#ifdef CONFIG_HAS_CUSTOM_SPL_MALLOC_START
-#define SYS_SPL_MALLOC_START		CONFIG_CUSTOM_SYS_SPL_MALLOC_ADDR
+#ifdef CONFIG_SPL_HAS_CUSTOM_MALLOC_START
+#define SPL_SYS_MALLOC_START		CONFIG_SPL_CUSTOM_SYS_MALLOC_ADDR
 #else
-#define SYS_SPL_MALLOC_START		(CONFIG_SPL_BSS_START_ADDR + \
+#define SPL_SYS_MALLOC_START		(CONFIG_SPL_BSS_START_ADDR + \
 					 CONFIG_SPL_BSS_MAX_SIZE)
 #endif