configs: Re-sync almost all of cmd/Kconfig

This syncs up the current cmd/Kconfig and include/configs/ files with the
only exception being CMD_NAND.  Due to how we have used this historically
we need to take further care here when converting.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/v38b_defconfig b/configs/v38b_defconfig
index cc3d802..3dadfcc 100644
--- a/configs/v38b_defconfig
+++ b/configs/v38b_defconfig
@@ -1,4 +1,8 @@
 CONFIG_PPC=y
 CONFIG_MPC5xxx=y
 CONFIG_TARGET_V38B=y
+CONFIG_CMD_I2C=y
+CONFIG_CMD_USB=y
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_PING=y