Tools: Decouple output and template of template tool

Templates are found by suffixing ".template " to "output".
This patch adds a new item "templates" in generated file list
to explicitly show where templates are so that outputs and templates
can have different paths.

Change-Id: Ic1ad242681fccdd5b8cad01e2f3ac15726b115ab
Signed-off-by: Kevin Peng <kevin.peng@arm.com>
diff --git a/tools/tfm_parse_manifest_list.py b/tools/tfm_parse_manifest_list.py
index 9ea5f7d..9805cc5 100644
--- a/tools/tfm_parse_manifest_list.py
+++ b/tools/tfm_parse_manifest_list.py
@@ -150,7 +150,7 @@
 
     for file in file_list:
         outfile_name = os.path.expandvars(file["output"])
-        templatefile_name = outfile_name + '.template'
+        templatefile_name = os.path.expandvars(file["template"])
 
         if OUT_DIR is not None:
             outfile_name = os.path.join(OUT_DIR, outfile_name)