Recent regression in commit 795bb37a39
that skipped clearing some internal buffers, caused pretty significant
security implications:
478212631/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-5143269947539456
478212631/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-5389230846312448
478212631/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-4732512093143040
478212631/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-4791771971518464
478212631/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-6030282833854464
478301104/clusterfuzz-testcase-minimized-fuzzer_set_property_MPV_FORMAT_STRING_1-5053287094353920
Found-by: https://github.com/google/oss-fuzz/tree/master/projects/mpv
None of which were found by FFmpeg's fuzzing infrastructure, so update
the SWS fuzzer to account for that.
Signed-off-by: Kacper Michajłow <kasper93@gmail.com>