Add libprotobuf-cpp-lite-rtti target for the platform.
Add libprotobuf-cpp-lite-rtti target for the platform.

When linking against libprotobuf-lite, if your program is compiled with
-frtti, you need the typeinfo for google::protobuf::MessageLite. On the
other hand, if your program is compiled with -fno-rtti, you need
libprotobuf-lite to be compiled with -DGOOGLE_PROTOBUF_NO_RTTI so the
library headers don't attempt to use the type information.

To allow old programs compiled with -fno-rtti and new programs compiled
with -frtti coexists, this patch introduces a new target
libprotobuf-cpp-lite-rtti enabling -frtti on libprotobuf-cpp-lite
similar to the existing libprotobuf-cpp-full-gnustl-rtti.

Bug: 23084776
Change-Id: I85d5e794071e69500eaf54c42b1c70580177af70
Test: `mma external/protobuf`

MonkeyZZZZ/platform_external_protobuf,MonkeyZZZZ/platform_external_protobuf,MonkeyZZZZ/platform_external_protobuf,MonkeyZZZZ/platform_external_protobuf,MonkeyZZZZ/platform_external_protobuf