env: Simplify Makefile using $(SPL_TPL_)

Add Kconfig options SPL_ENV_* and TPL_ENV_* and simplify Makefile.
This allows SPL/TPL image has different environment setting from
full feature U-Boot.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/env/Makefile b/env/Makefile
index fa635c8..90144d6 100644
--- a/env/Makefile
+++ b/env/Makefile
@@ -14,41 +14,23 @@
 obj-$(CONFIG_ENV_IS_IN_EEPROM) += embedded.o
 extra-$(CONFIG_ENV_IS_IN_FLASH) += embedded.o
 obj-$(CONFIG_ENV_IS_IN_NVRAM) += embedded.o
-obj-$(CONFIG_ENV_IS_IN_FLASH) += flash.o
-obj-$(CONFIG_ENV_IS_IN_MMC) += mmc.o
-obj-$(CONFIG_ENV_IS_IN_FAT) += fat.o
-obj-$(CONFIG_ENV_IS_IN_EXT4) += ext4.o
-obj-$(CONFIG_ENV_IS_IN_NAND) += nand.o
 obj-$(CONFIG_ENV_IS_IN_NVRAM) += nvram.o
 obj-$(CONFIG_ENV_IS_IN_ONENAND) += onenand.o
 obj-$(CONFIG_ENV_IS_IN_SATA) += sata.o
-obj-$(CONFIG_ENV_IS_IN_SPI_FLASH) += sf.o
 obj-$(CONFIG_ENV_IS_IN_REMOTE) += remote.o
 obj-$(CONFIG_ENV_IS_IN_UBI) += ubi.o
-obj-$(CONFIG_ENV_IS_NOWHERE) += nowhere.o
+else
+obj-$(CONFIG_$(SPL_TPL_)ENV_SUPPORT) += attr.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_SUPPORT) += flags.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_SUPPORT) += callback.o
 endif
 
-ifdef CONFIG_SPL_BUILD
-obj-$(CONFIG_ENV_IS_IN_FLASH) += flash.o
-# environment
-ifdef CONFIG_TPL_BUILD
-obj-$(CONFIG_TPL_ENV_SUPPORT) += attr.o
-obj-$(CONFIG_TPL_ENV_SUPPORT) += flags.o
-obj-$(CONFIG_TPL_ENV_SUPPORT) += callback.o
-else
-obj-$(CONFIG_SPL_ENV_SUPPORT) += attr.o
-obj-$(CONFIG_SPL_ENV_SUPPORT) += flags.o
-obj-$(CONFIG_SPL_ENV_SUPPORT) += callback.o
-endif
-ifneq ($(CONFIG_TPL_ENV_SUPPORT)$(CONFIG_SPL_ENV_SUPPORT),)
-obj-$(CONFIG_ENV_IS_NOWHERE) += nowhere.o
-obj-$(CONFIG_ENV_IS_IN_MMC) += mmc.o
-obj-$(CONFIG_ENV_IS_IN_FAT) += fat.o
-obj-$(CONFIG_ENV_IS_IN_EXT4) += ext4.o
-obj-$(CONFIG_ENV_IS_IN_NAND) += nand.o
-obj-$(CONFIG_ENV_IS_IN_SPI_FLASH) += sf.o
-obj-$(CONFIG_ENV_IS_IN_FLASH) += flash.o
-endif
-endif
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_NOWHERE) += nowhere.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_MMC) += mmc.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_FAT) += fat.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_EXT4) += ext4.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_NAND) += nand.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_SPI_FLASH) += sf.o
+obj-$(CONFIG_$(SPL_TPL_)ENV_IS_IN_FLASH) += flash.o
 
 CFLAGS_embedded.o := -Wa,--no-warn -DENV_CRC=$(shell tools/envcrc 2>/dev/null)