Disable dtrace probes on Windows.

Apparently, in Win10, dtrace is avaialable, but it does not work with
MariaDB user probes

cmake/dtrace.cmake

@@ -43,7 +43,8 @@ MACRO(CHECK_DTRACE)
  IF(DTRACE AND NOT CMAKE_SYSTEM_NAME MATCHES "FreeBSD"
      AND NOT BUGGY_GCC_NO_DTRACE_MODULES
      AND NOT BUGGY_LINUX_DTRACE
-     AND NOT CMAKE_SYSTEM_NAME MATCHES "SunOS")
+     AND NOT CMAKE_SYSTEM_NAME MATCHES "SunOS"
+     AND NOT WIN32)
    SET(ENABLE_DTRACE ON CACHE BOOL "Enable dtrace")
  ENDIF()
  # On GNU/Hurd, dtrace is not supported