check: patch internal check copy some more so that failures actually fail
check: patch internal check copy some more so that failures actually fail

Include unistd.h so that _POSIX_VERSION is actually defined when
it should be defined. Without that, stuff like fail_if(1) doesn't
actually fail, presumably because other parts of the code do include
unistd.h and then have _POSIX_VERSION defined.

Fixes #604565 even more.

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