Add dhcp-6.8.2 to manifest

Add the newly created dhcp-6.8.2 to the manifest.

Bug: 22956197
TEST: repo sync and verify that external/dhcp-6.8.2/ is created.
Change-Id: I3829928643d38f132def415f75f42469fd2183b7

default.xml

@@ -121,6 +121,7 @@
   <project path="external/deqp" name="platform/external/deqp" groups="pdk-fs" />
   <project path="external/dexmaker" name="platform/external/dexmaker" groups="pdk-cw-fs,pdk-fs" />
   <project path="external/dhcpcd" name="platform/external/dhcpcd" groups="pdk-cw-fs,pdk-fs" />
+  <project path="external/dhcpcd-6.8.2" name="platform/external/dhcpcd-6.8.2" />
   <project path="external/dnsmasq" name="platform/external/dnsmasq" groups="pdk" />
   <project path="external/doclava" name="platform/external/doclava" groups="pdk-cw-fs,pdk-fs" />
   <project path="external/droiddriver" name="platform/external/droiddriver" groups="pdk-cw-fs,pdk-fs" />