Convert CONFIG_USE_BOOTCOMMAND et al to Kconfig

This converts the following to Kconfig:
   CONFIG_USE_BOOTCOMMAND
   CONFIG_BOOTCOMMAND
   CONFIG_RAMBOOTCOMMAND
   CONFIG_NFSBOOTCOMMAND

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/ls1046aqds_defconfig b/configs/ls1046aqds_defconfig
index a8d9441..caf602c 100644
--- a/configs/ls1046aqds_defconfig
+++ b/configs/ls1046aqds_defconfig
@@ -22,7 +22,7 @@
 CONFIG_BOOTDELAY=10
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="console=ttyS0,115200 root=/dev/ram0 earlycon=uart8250,mmio,0x21c0500 mtdparts=60000000.nor:2m@0x100000(nor_bank0_uboot),40m@0x1100000(nor_bank0_fit),7m(nor_bank0_user),2m@0x4100000(nor_bank4_uboot),40m@0x5100000(nor_bank4_fit),-(nor_bank4_user);7e800000.flash:4m(nand_uboot),36m(nand_kernel),472m(nand_free);spi0.0:2m(uboot),14m(free)"
-# CONFIG_USE_BOOTCOMMAND is not set
+CONFIG_BOOTCOMMAND="run distro_bootcmd; run nor_bootcmd; env exists secureboot && esbc_halt;;"
 CONFIG_MISC_INIT_R=y
 CONFIG_CMD_BOOTZ=y
 CONFIG_CMD_IMLS=y