Remove external/libnl and external/nfacct

These projects weren't quite ready to be included in the manifest.
Removing for now.
Change-Id: Ica4cf732545a6a0ca64c55a4c48bdadd28637cc8

default.xml

@@ -151,7 +151,6 @@
   <project path="external/libmtp" name="platform/external/libmtp" />
   <project path="external/libnfc-nci" name="platform/external/libnfc-nci" groups="pdk" />
   <project path="external/libnfc-nxp" name="platform/external/libnfc-nxp" groups="pdk" />
-  <project path="external/libnl" name="platform/external/libnl" />
   <project path="external/libnl-headers" name="platform/external/libnl-headers" groups="pdk" />
   <project path="external/libogg" name="platform/external/libogg" />
   <project path="external/libpcap" name="platform/external/libpcap" />
@@ -186,7 +185,6 @@
   <project path="external/netcat" name="platform/external/netcat" />
   <project path="external/netperf" name="platform/external/netperf" />
   <project path="external/neven" name="platform/external/neven" />
-  <project path="external/nfacct" name="platform/external/nfacct" />
   <project path="external/nist-pkits" name="platform/external/nist-pkits" />
   <project path="external/nist-sip" name="platform/external/nist-sip" />
   <project path="external/noto-fonts" name="platform/external/noto-fonts" />