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/configs/display5_factory_defconfig b/configs/display5_factory_defconfig
index 672b76e..fbec341 100644
--- a/configs/display5_factory_defconfig
+++ b/configs/display5_factory_defconfig
@@ -35,7 +35,7 @@
 CONFIG_USE_BOOTCOMMAND=y
 CONFIG_BOOTCOMMAND="echo SDP Display5 recovery"
 CONFIG_MISC_INIT_R=y
-CONFIG_SYS_SPL_MALLOC=y
+CONFIG_SPL_SYS_MALLOC=y
 # CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR is not set
 CONFIG_SPL_DMA=y
 CONFIG_SPL_I2C=y