Move curve25519 code to third_party/fiat.

This change doesn't actually introduce any Fiat code yet. It sets up the
directory structure to make the diffs in the next change clearer.

Change-Id: I38a21fb36b18a08b0907f9d37b7ef5d7d3137ede
Reviewed-on: https://boringssl-review.googlesource.com/22624
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/util/generate_build_files.py b/util/generate_build_files.py
index 738484d..4b4a899 100644
--- a/util/generate_build_files.py
+++ b/util/generate_build_files.py
@@ -587,7 +587,8 @@
 
 def main(platforms):
   cmake = ExtractVariablesFromCMakeFile(os.path.join('src', 'sources.cmake'))
-  crypto_c_files = FindCFiles(os.path.join('src', 'crypto'), NoTestsNorFIPSFragments)
+  crypto_c_files = (FindCFiles(os.path.join('src', 'crypto'), NoTestsNorFIPSFragments) +
+                    FindCFiles(os.path.join('src', 'third_party', 'fiat'), NoTestsNorFIPSFragments))
   fips_fragments = FindCFiles(os.path.join('src', 'crypto', 'fipsmodule'), OnlyFIPSFragments)
   ssl_source_files = FindCFiles(os.path.join('src', 'ssl'), NoTests)
   tool_c_files = FindCFiles(os.path.join('src', 'tool'), NoTests)
@@ -638,8 +639,9 @@
           NotSSLHeaderFiles))
 
   ssl_internal_h_files = FindHeaderFiles(os.path.join('src', 'ssl'), NoTests)
-  crypto_internal_h_files = FindHeaderFiles(
-      os.path.join('src', 'crypto'), NoTests)
+  crypto_internal_h_files = (
+      FindHeaderFiles(os.path.join('src', 'crypto'), NoTests) +
+      FindHeaderFiles(os.path.join('src', 'third_party', 'fiat'), NoTests))
 
   files = {
       'crypto': crypto_c_files,