CYGWIN,MSYS: Build CMake with OpenSSL by default

Extend the changes from commit 190a5fdffd (Automatically use OpenSSL by
default on Linux and FreeBSD if available, 2016-02-26, v3.6.0-rc1~301^2)
and commit dd3e476786 (OpenSSL: Issue an error if OpenSSL is not found,
2019-07-17, v3.16.0-rc1~379^2) to cover builds targeting the CYGWIN and
MSYS runtime platforms.

Source/Modules/CMakeBuildUtilities.cmake

@@ -150,7 +150,7 @@ else()
   endif()
   set(_CMAKE_USE_OPENSSL_DEFAULT OFF)
   if(NOT DEFINED CMAKE_USE_OPENSSL AND NOT WIN32 AND NOT APPLE
-      AND CMAKE_SYSTEM_NAME MATCHES "(Linux|FreeBSD)")
+      AND CMAKE_SYSTEM_NAME MATCHES "(Linux|FreeBSD|CYGWIN|MSYS)")
     set(_CMAKE_USE_OPENSSL_DEFAULT ON)
   endif()
   option(CMAKE_USE_OPENSSL "Use OpenSSL." ${_CMAKE_USE_OPENSSL_DEFAULT})