fate: quote file paths in movie/amovie filtergraphs.

This should avoid some nasty ':' escaping.

tests/fate/filter.mak

@@ -55,12 +55,12 @@ SCENEDETECT_DEPS = FFPROBE LAVFI_INDEV MOVIE_FILTER SELECT_FILTER SCALE_FILTER \
                    AVCODEC MOV_DEMUXER SVQ3_DECODER ZLIB
 FATE_METADATA_FILTER-$(call ALLYES, $(SCENEDETECT_DEPS)) += fate-filter-metadata-scenedetect
 fate-filter-metadata-scenedetect: SRC = $(SAMPLES)/svq3/Vertical400kbit.sorenson3.mov
-fate-filter-metadata-scenedetect: CMD = run $(FILTER_METADATA_COMMAND) "sws_flags=+accurate_rnd+bitexact;movie=$(SRC),select=gt(scene\,.4)"
+fate-filter-metadata-scenedetect: CMD = run $(FILTER_METADATA_COMMAND) "sws_flags=+accurate_rnd+bitexact;movie='$(SRC)',select=gt(scene\,.4)"
 
 SILENCEDETECT_DEPS = FFPROBE LAVFI_INDEV AMOVIE_FILTER AMR_DEMUXER AMRWB_DECODER
 FATE_METADATA_FILTER-$(call ALLYES, $(SILENCEDETECT_DEPS)) += fate-filter-metadata-silencedetect
 fate-filter-metadata-silencedetect: SRC = $(SAMPLES)/amrwb/seed-12k65.awb
-fate-filter-metadata-silencedetect: CMD = run $(FILTER_METADATA_COMMAND) "amovie=$(SRC),silencedetect=d=.1"
+fate-filter-metadata-silencedetect: CMD = run $(FILTER_METADATA_COMMAND) "amovie='$(SRC)',silencedetect=d=.1"
 
 FATE_SAMPLES_FFPROBE += $(FATE_METADATA_FILTER-yes)