Define NOMINMAX across the entire project.

This fixes the standalone build on Windows and matches Chromium.

Change-Id: I194f53e0a610c5ae9cef53c826b22f7bded5f357
Reviewed-on: https://boringssl-review.googlesource.com/4201
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8ee4d3d..dd7183e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -63,6 +63,7 @@
   set(CMAKE_CXX_FLAGS "-Wall -WX ${MSVC_DISABLED_WARNINGS_STR}")
   add_definitions(-D_HAS_EXCEPTIONS=0)
   add_definitions(-DWIN32_LEAN_AND_MEAN)
+  add_definitions(-DNOMINMAX)
 endif()
 
 if((CMAKE_COMPILER_IS_GNUCXX AND CMAKE_C_COMPILER_VERSION VERSION_GREATER "4.7.99") OR
diff --git a/tool/digest.cc b/tool/digest.cc
index f95f412..4acf97c 100644
--- a/tool/digest.cc
+++ b/tool/digest.cc
@@ -32,7 +32,6 @@
 #define O_BINARY 0
 #endif
 #else
-#define NOMINMAX
 #pragma warning(push, 3)
 #include <windows.h>
 #pragma warning(pop)
diff --git a/tool/transport_common.cc b/tool/transport_common.cc
index 9400fe6..8d6013b 100644
--- a/tool/transport_common.cc
+++ b/tool/transport_common.cc
@@ -31,7 +31,6 @@
 #include <sys/socket.h>
 #include <unistd.h>
 #else
-#define NOMINMAX
 #include <io.h>
 #pragma warning(push, 3)
 #include <winsock2.h>