ti: am43xx_evm: Switch to DISTRO_BOOT only

Remove the environment support for various legacy boot methods.  With
this, we will now default to booting any distribution that follows the
generic distro boot framework and no longer attempt to boot various
legacy (to this SoC) scripts/etc.

Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210701132612.7559-1-trini@konsulko.com
diff --git a/configs/am43xx_evm_usbhost_boot_defconfig b/configs/am43xx_evm_usbhost_boot_defconfig
index b1be027..ae23343 100644
--- a/configs/am43xx_evm_usbhost_boot_defconfig
+++ b/configs/am43xx_evm_usbhost_boot_defconfig
@@ -11,7 +11,7 @@
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_SPL_LOAD_FIT=y
 # CONFIG_USE_SPL_FIT_GENERATOR is not set
-# CONFIG_USE_BOOTCOMMAND is not set
+CONFIG_BOOTCOMMAND="run findfdt; run finduuid; run distro_bootcmd"
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 # CONFIG_MISC_INIT_R is not set
 CONFIG_SPL_MTD_SUPPORT=y