Protocol "smtps" is not supported (or) Disabled in libcurl

Please follow the steps below:

  1. in ./poky/meta/recipes-support/curl/curl_7.61.0.bb, add the rtsp rtmp function like below:
    PACKAGECONFIG ??= “${@bb.utils.filter(‘DISTRO_FEATURES’, ‘ipv6’, d)} gnutls proxy threaded-resolver zlib libssh2 smtp rtsp rtmpdump”
  2. copy the folder ./meta-openembedded/meta-multimedia/recipes-multimedia/rtmpdump/ to ./meta-swi/common/recipes-multimedia/
  3. in ./meta-swi/meta-swi-mdm9x28/recipes-core/images/mdm9x28-image.inc, add the following:
    IMAGE_INSTALL_append = " rtmpdump"
    4.in ./meta-swi/meta-swi-mdm9x28/recipes-core/images/mdm9x28-image.inc, DO NOT add the following:
    IMAGE_INSTALL_append = " ffmpeg"
  4. make the yocto image and download to your module

Thank you so much jyijyi
finally i got rtmp.