avfilter/vf_vpp_qsv: Don't overrun stack array

8b83dad825 added another potentially used
video enhancement filter without increasing a define for the number of
such options which is used as the size of stack array. This can lead to
a buffer overrun if all filters are used simultaneously. So increase
said number.

Fixes Coverity ticket #1489775.

Reviewed-by: Linjie Fu <linjie.justin.fu@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavfilter/vf_vpp_qsv.c

@@ -42,7 +42,7 @@
 #define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM)
 
 /* number of video enhancement filters */
-#define ENH_FILTERS_COUNT (7)
+#define ENH_FILTERS_COUNT (8)
 #define QSV_HAVE_ROTATION       QSV_VERSION_ATLEAST(1, 17)
 #define QSV_HAVE_MIRRORING      QSV_VERSION_ATLEAST(1, 19)
 #define QSV_HAVE_SCALING_CONFIG QSV_VERSION_ATLEAST(1, 19)