Config: support rtmp_to_rtsp. #295

Job	Run time
multiple-arch-aarch64	5m 51s
multiple-arch-armv7	5m 41s
cygwin64-cache	2m 48s
utest-regression-blackbox-test	5m 1s
fast	1s
cygwin64	6m 56s
build-ubuntu18	1m 34s
build-centos7	2m 11s
build-ubuntu20	1m 48s
build-ubuntu16	1m 44s
build-cross-arm	2m 23s
build-cross-aarch64	2m 28s
coverage	2m 40s
multiple-arch-amd64	1m 34s
test-done	1s
	42m 41s

Provide feedback