Add external/kotlinc to the manifest

Test: syncs
Bug: 65219535
Change-Id: I524b9b89ee108b89a7c4ac4f63d69f50257a9d35

default.xml

@@ -191,6 +191,7 @@
   <project path="external/junit-params" name="platform/external/junit-params" groups="pdk" />
   <project path="external/kernel-headers" name="platform/external/kernel-headers" groups="pdk-cw-fs,pdk-fs" />
   <project path="external/kmod" name="platform/external/kmod" groups="pdk" />
+  <project path="external/kotlinc" name="platform/external/kotlinc" groups="pdk" />
   <project path="external/ksoap2" name="platform/external/ksoap2" groups="pdk-cw-fs,pdk-fs" />
   <project path="external/libavc" name="platform/external/libavc" groups="pdk" />
   <project path="external/libbackup" name="platform/external/libbackup" groups="pdk" />