Import patch-bsd-defines from FreeBSD ports [1]

As noted in the patch description:
* Add DragonFly and GNU/kFreeBSD support.
* Implement GetThreadCount() for BSDs.

1. https://svnweb.freebsd.org/ports/head/devel/googletest/files/patch-bsd-defines?revision=488934

Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>

googletest/test/googletest-port-test.cc

@@ -286,7 +286,9 @@ TEST(FormatCompilerIndependentFileLocationTest, FormatsUknownFileAndLine) {
   EXPECT_EQ("unknown file", FormatCompilerIndependentFileLocation(nullptr, -1));
 }
 
-#if GTEST_OS_LINUX || GTEST_OS_MAC || GTEST_OS_QNX || GTEST_OS_FUCHSIA
+#if GTEST_OS_LINUX || GTEST_OS_MAC || GTEST_OS_QNX || GTEST_OS_FUCHSIA || \
+    GTEST_OS_DRAGONFLY || GTEST_OS_FREEBSD || GTEST_OS_GNU_KFREEBSD || \
+    GTEST_OS_NETBSD || GTEST_OS_OPENBSD
 void* ThreadFunc(void* data) {
   internal::Mutex* mutex = static_cast<internal::Mutex*>(data);
   mutex->Lock();