Switch to toybox dd.

Change-Id: I8a0256e8804d0118ae39c63b15a85d9ad5a6ab84
diff --git a/ui/build/paths/config.go b/ui/build/paths/config.go
index b3e871f..eba823a 100644
--- a/ui/build/paths/config.go
+++ b/ui/build/paths/config.go
@@ -87,7 +87,6 @@
 // run during the build. For more documentation, see path_interposer.go .
 var Configuration = map[string]PathConfig{
 	"bash":           Allowed,
-	"dd":             Allowed,
 	"diff":           Allowed,
 	"dlv":            Allowed,
 	"expr":           Allowed,