env: Finish migration of common ENV options

- In ARMv8 NXP Layerscape platforms we also need to make use of
  CONFIG_SYS_RELOC_GD_ENV_ADDR now, do so.
- On ENV_IS_IN_REMOTE, CONFIG_ENV_OFFSET is never used, drop the define
  to 0.
- Add Kconfig entry for ENV_ADDR.
- Make ENV_ADDR / ENV_OFFSET depend on the env locations that use it.
- Add ENV_xxx_REDUND options that depend on their primary option and
  SYS_REDUNDAND_ENVIRONMENT
- On a number of PowerPC platforms, use SPL_ENV_ADDR not CONFIG_ENV_ADDR
  for the pre-main-U-Boot environment location.
- On ENV_IS_IN_SPI_FLASH, check not for CONFIG_ENV_ADDR being set but
  rather it being non-zero, as it will now be zero by default.
- Rework the env_offset absolute in env/embedded.o to not use
  CONFIG_ENV_OFFSET as it was the only use of ENV_OFFSET within
  ENV_IS_IN_FLASH.
- Migrate all platforms.

Cc: Wolfgang Denk <wd@denx.de>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: uboot-stm32@st-md-mailman.stormreply.com
Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/configs/cm_t54_defconfig b/configs/cm_t54_defconfig
index f857c04..11b34d9 100644
--- a/configs/cm_t54_defconfig
+++ b/configs/cm_t54_defconfig
@@ -4,7 +4,7 @@
 CONFIG_TARGET_CM_T54=y
 CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC=16296
 CONFIG_ENV_SIZE=0x4000
-CONFIG_ENV_OFFSET=0xc0000
+CONFIG_ENV_OFFSET=0xC0000
 CONFIG_SPL=y
 CONFIG_SPL_TEXT_BASE=0x40300000
 CONFIG_DISTRO_DEFAULTS=y
@@ -33,6 +33,7 @@
 CONFIG_CMD_EXT4_WRITE=y
 CONFIG_ENV_IS_IN_MMC=y
 CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
+CONFIG_ENV_OFFSET_REDUND=0xC4000
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG=y
 CONFIG_SCSI_AHCI=y