Fix ToolchainLdflags calls

Instead of having the baseCompiler adjust the Ldflags, teach
objectLinker about ToolchainLdflags. And don't assume that
ToolchainLdflags will work for Clang too, add a ToolchainClangLdflags
call.

Change-Id: I5f546e46f32edf3fcf75a44bee2c5ee103bc5de3
3 files changed