Remove external/dropbear

Change-Id: I9d29ae65466aa4c17a02e833e30c0cb6b2d895c6
diff --git a/default.xml b/default.xml
index 404b731..1bf63b5 100644
--- a/default.xml
+++ b/default.xml
@@ -99,7 +99,6 @@
   <project path="external/dhcpcd" name="platform/external/dhcpcd" />
   <project path="external/dnsmasq" name="platform/external/dnsmasq" groups="pdk" />
   <project path="external/doclava" name="platform/external/doclava" />
-  <project path="external/dropbear" name="platform/external/dropbear" />
   <project path="external/e2fsprogs" name="platform/external/e2fsprogs" groups="pdk" />
   <project path="external/easymock" name="platform/external/easymock" />
   <project path="external/eclipse-basebuilder" name="platform/external/eclipse-basebuilder" />