[libc] Add fully-qualified target names.

Only targets setup by the special LLVM libc rules now have fully
qualified names. The naming style is similar to fully qualified names in
Python.

Reviewers: abrachet, PaulkaToast, phosek

Differential Revision: https://reviews.llvm.org/D77340

Author: Siva Chandra Reddy

libc/CMakeLists.txt

@@ -23,9 +23,9 @@ include(CMakeParseArguments)
 include(LLVMLibCRules)
 include(LLVMLibCCheckCpuFeatures)
 
-add_subdirectory(src)
-add_subdirectory(config)
 add_subdirectory(include)
+add_subdirectory(config)
+add_subdirectory(src)
 add_subdirectory(utils)
 
 # The loader can potentially depend on the library components so add it