gen7_mfd: Optimise start code search
gen7_mfd: Optimise start code search

Code inspired from GStreamer

See https://bugs.freedesktop.org/show_bug.cgi?id=89507

Signed-off-by: Olivier Crete <86e32882ba3951d68bd2d06702dd09a9d6fd15fe@collabora.com>

uartie/vaapi-intel-driver,chenxianqin/vaapi-intel-driver,01org/iotg-lin-gfx-va-driver,gbeauchesne/libva-intel-driver,01org/iotg-lin-gfx-va-driver,chenxianqin/vaapi-intel-driver,uartie/vaapi-intel-driver,uartie/vaapi-intel-driver,gbeauchesne/libva-intel-driver,uartie/vaapi-intel-driver,gbeauchesne/libva-intel-driver,01org/iotg-lin-gfx-va-driver,01org/iotg-lin-gfx-va-driver,chenxianqin/vaapi-intel-driver,gbeauchesne/libva-intel-driver,uartie/vaapi-intel-driver,gbeauchesne/libva-intel-driver,chenxianqin/vaapi-intel-driver,chenxianqin/vaapi-intel-driver,01org/iotg-lin-gfx-va-driver