configure: check VTPixelTransferSessionCreate for scale_vt

It's available on macOS since 10.8, but not available on iOS until
16.0.

Reported and tested by xufuji456.

Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>

configure

@@ -3836,7 +3836,7 @@ zmq_filter_deps="libzmq"
 zoompan_filter_deps="swscale"
 zscale_filter_deps="libzimg const_nan"
 scale_vaapi_filter_deps="vaapi"
-scale_vt_filter_deps="videotoolbox"
+scale_vt_filter_deps="videotoolbox VTPixelTransferSessionCreate"
 scale_vulkan_filter_deps="vulkan spirv_compiler"
 vpp_qsv_filter_deps="libmfx"
 vpp_qsv_filter_select="qsvvpp"
@@ -6501,6 +6501,7 @@ check_headers termios.h
 check_headers unistd.h
 check_headers valgrind/valgrind.h
 check_func_headers VideoToolbox/VTCompressionSession.h VTCompressionSessionPrepareToEncodeFrames -framework VideoToolbox
+check_func_headers VideoToolbox/VideoToolbox.h VTPixelTransferSessionCreate -framework VideoToolbox
 check_func_headers VideoToolbox/VideoToolbox.h VTPixelRotationSessionCreate -framework VideoToolbox
 check_headers windows.h
 check_headers asm/types.h