global: Rename SPL_TPL_ to PHASE_

Use PHASE_ as the symbol to select a particular XPL build. This means
that SPL_TPL_ is no-longer set.

Update the comment in bootstage to refer to this symbol, instead of
SPL_

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index db01041..ce05e20 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -34,9 +34,9 @@
 ifneq ($(mtd-y),)
 obj-$(CONFIG_SPL_MTD) += mtd.o
 endif
-obj-$(CONFIG_$(SPL_TPL_)NAND_SUPPORT) += nand/
+obj-$(CONFIG_$(PHASE_)NAND_SUPPORT) += nand/
 obj-$(CONFIG_SPL_ONENAND_SUPPORT) += onenand/
-obj-$(CONFIG_$(SPL_TPL_)SPI_FLASH_SUPPORT) += spi/
+obj-$(CONFIG_$(PHASE_)SPI_FLASH_SUPPORT) += spi/
 obj-$(CONFIG_SPL_UBI) += ubispl/
 
 endif
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 68b53dc..c8169cf 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -6,5 +6,5 @@
 obj-$(CONFIG_MTD_RAW_NAND) += raw/
 obj-$(CONFIG_MTD_SPI_NAND) += spi/
 else
-obj-$(CONFIG_$(SPL_TPL_)NAND_SUPPORT) += raw/
+obj-$(CONFIG_$(PHASE_)NAND_SUPPORT) += raw/
 endif
diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
index ca10ac7..b47a3d7 100644
--- a/drivers/mtd/nand/raw/Makefile
+++ b/drivers/mtd/nand/raw/Makefile
@@ -18,7 +18,7 @@
 				nand_macronix.o nand_micron.o \
 				nand_samsung.o nand_toshiba.o
 obj-$(CONFIG_SPL_NAND_IDENT) += nand_ids.o nand_timings.o
-obj-$(CONFIG_$(SPL_TPL_)NAND_INIT) += nand.o
+obj-$(CONFIG_$(PHASE_)NAND_INIT) += nand.o
 ifeq ($(CONFIG_SPL_ENV_SUPPORT),y)
 obj-$(CONFIG_ENV_IS_IN_NAND) += nand_util.o
 endif
diff --git a/drivers/mtd/spi/Makefile b/drivers/mtd/spi/Makefile
index 2a287a6..44e67cd 100644
--- a/drivers/mtd/spi/Makefile
+++ b/drivers/mtd/spi/Makefile
@@ -3,12 +3,12 @@
 # (C) Copyright 2006
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 
-obj-$(CONFIG_$(SPL_TPL_)DM_SPI_FLASH) += sf-uclass.o
+obj-$(CONFIG_$(PHASE_)DM_SPI_FLASH) += sf-uclass.o
 spi-nor-y := sf_probe.o spi-nor-ids.o
 
 ifdef CONFIG_XPL_BUILD
 obj-$(CONFIG_SPL_SPI_BOOT)	+= fsl_espi_spl.o
-ifeq ($(CONFIG_$(SPL_TPL_)SPI_FLASH_TINY),y)
+ifeq ($(CONFIG_$(PHASE_)SPI_FLASH_TINY),y)
 spi-nor-y += spi-nor-tiny.o
 else
 spi-nor-y += spi-nor-core.o
@@ -19,6 +19,6 @@
 
 obj-$(CONFIG_SPI_FLASH) += spi-nor.o
 obj-$(CONFIG_SPI_FLASH_DATAFLASH) += sf_dataflash.o
-obj-$(CONFIG_$(SPL_TPL_)SPI_FLASH_MTD) += sf_mtd.o
+obj-$(CONFIG_$(PHASE_)SPI_FLASH_MTD) += sf_mtd.o
 obj-$(CONFIG_SPI_FLASH_SANDBOX) += sandbox.o
-obj-$(CONFIG_$(SPL_TPL_)BOOTDEV_SPI_FLASH) += sf_bootdev.o
+obj-$(CONFIG_$(PHASE_)BOOTDEV_SPI_FLASH) += sf_bootdev.o