Enable to use BH_VPRINTF macro for platform Linux/Windows/Darwin/VxWorks to redirect the stdout output from platform os_printf/os_vprintf, or the wasi output from wasm app to the vprintf like callback function specified by BH_VPRINTF macro of cmake WAMR_BH_VPRINTF variable.
Signed-off-by: Wenyong Huang <wenyong.huang@intel.com>