Set -Wframe-larger-than=25344 for a typical cmake clang compile.

This ensures that in the "usual" development process building and
running the tests will enforce this stack limit, which is encountered
in google3. This will prevent future development from adding code
and tests which blow over this limit and break google3

Change-Id: If722c7029cca63eb7d1e80de4b640b84839bb020
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/66867
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: Bob Beck <bbe@google.com>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 77ba873..685b7b4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -141,7 +141,7 @@
   endif()
 
   if(CLANG)
-    set(C_CXX_FLAGS "${C_CXX_FLAGS} -Wnewline-eof -fcolor-diagnostics")
+    set(C_CXX_FLAGS "${C_CXX_FLAGS} -Wnewline-eof -fcolor-diagnostics -Wframe-larger-than=25344")
   else()
     # GCC (at least 4.8.4) has a bug where it'll find unreachable free() calls
     # and declare that the code is trying to free a stack pointer.