schema compile REFACTOR split implementing and compiling schemas

Difference being that implementing checks that a new
module can be implemented and performs one-time compilation
tasks such as compiling identities and adding its references
to augment and eviation target modules, which are also
implemented. Compilation then actually creates the compiled
module and can be performed in each recompilation.
diff --git a/src/schema_compile_amend.h b/src/schema_compile_amend.h
index 3dca22c..0ad49b4 100644
--- a/src/schema_compile_amend.h
+++ b/src/schema_compile_amend.h
@@ -156,11 +156,11 @@
 LY_ERR lys_precompile_own_deviations(struct lysc_ctx *ctx);
 
 /**
- * @brief Compile top-level augments and deviations in a module and all its submodules.
- * Adds the module reference to the target modules and if not implemented, implement them.
+ * @brief Add references to target modules of top-level augments and deviations in a module and all its submodules.
+ * Adds the module reference to the target modules and if not implemented, implement them (but not compile).
  *
  * @param[in] mod Module to process.
- * @param[in] unres Global unres to use.
+ * @param[in,out] unres Global unres to use.
  * @return LY_SUCCESS on success.
  * @return LY_ERECOMPILE on required recompilation.
  * @return LY_ERR on error.