win32: define __MSVCRT_VERSION__ when compiling with MingW, for __stat64
win32: define __MSVCRT_VERSION__ when compiling with MingW, for __stat64

Need to define this when using MingW, so that the includes provide
__stat64 and friends. We need at least Windows XP SP2 for this.
Fixes #568632.

surround-io/gstreamer,jpxiong/gstreamer,krichter722/gstreamer,justinjoy/gstreamer,cablelabs/gstreamer,krieger-od/gstreamer,surround-io/gstreamer,magcius/gstreamer,centricular/gstreamer,cfoch/gstreamer,surround-io/gstreamer,lovebug356/gstreamer,collects/gstreamer,mrchapp/gstreamer,mparis/gstreamer,magcius/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,collects/gstreamer,Lachann/gstreamer,Lachann/gstreamer,cfoch/gstreamer,cfoch/gstreamer,collects/gstreamer,mparis/gstreamer,cablelabs/gstreamer,justinjoy/gstreamer,Distrotech/gstreamer,ylatuya/gstreamer,ylatuya/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,mrchapp/gstreamer,cablelabs/gstreamer,lubosz/gstreamer,Distrotech/gstreamer,surround-io/gstreamer,Lachann/gstreamer,ylatuya/gstreamer,cablelabs/gstreamer,lovebug356/gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,krichter722/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,drothlis/gstreamer,lubosz/gstreamer,jpxiong/gstreamer,jpakkane/gstreamer,shelsonjava/gstreamer,drothlis/gstreamer,krieger-od/gstreamer,shelsonjava/gstreamer,ylatuya/gstreamer,drothlis/gstreamer,ahmedammar/platform_external_gst_gstreamer,centricular/gstreamer,krieger-od/gstreamer,ensonic/gstreamer,lovebug356/gstreamer,jpakkane/gstreamer,justinjoy/gstreamer,ensonic/gstreamer,centricular/gstreamer,ensonic/gstreamer,ahmedammar/platform_external_gst_gstreamer,justinjoy/gstreamer,Lachann/gstreamer,Distrotech/gstreamer,Lachann/gstreamer,mparis/gstreamer,magcius/gstreamer,mrchapp/gstreamer,ensonic/gstreamer,drothlis/gstreamer,ensonic/gstreamer,krichter722/gstreamer,magcius/gstreamer,StreamUtils/gstreamer,ahmedammar/platform_external_gst_gstreamer,lubosz/gstreamer,magcius/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,ahmedammar/platform_external_gst_gstreamer,surround-io/gstreamer,mparis/gstreamer,mrchapp/gstreamer,justinjoy/gstreamer,centricular/gstreamer,lovebug356/gstreamer,mrchapp/gstreamer,collects/gstreamer,centricular/gstreamer,mparis/gstreamer,Distrotech/gstreamer,jpakkane/gstreamer,ahmedammar/platform_external_gst_gstreamer,jpakkane/gstreamer,drothlis/gstreamer,shelsonjava/gstreamer,lubosz/gstreamer,shelsonjava/gstreamer,ylatuya/gstreamer,Distrotech/gstreamer,cfoch/gstreamer,lubosz/gstreamer,collects/gstreamer,StreamUtils/gstreamer,lovebug356/gstreamer,jpxiong/gstreamer,cablelabs/gstreamer