Fix Fiat path.

(I'm not sure why this built anywhere, but it did.)

Change-Id: I47e5b9b689c597e38a74104ac9ddcadfc2fb063d
Reviewed-on: https://boringssl-review.googlesource.com/31644
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index 86da207..2690552 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -387,7 +387,7 @@
   x509v3/v3_skey.c
   x509v3/v3_sxnet.c
   x509v3/v3_utl.c
-  ../../third_party/fiat/curve25519.c
+  ../third_party/fiat/curve25519.c
 
   $<TARGET_OBJECTS:fipsmodule>