package/minimodem: new package

package/minimodem: new package

Minimodem is a command-line program which decodes (or generates)
audio modem tones at any specified baud rate, using various
framing protocols. It acts a general-purpose software FSK modem,
and includes support for various standard FSK protocols such as
Bell103, Bell202, RTTY, TTY/TDD NOAA SAME, and Caller-ID.

Signed-off-by: Alexander Kurz <akurz@blala.de>
[Thomas:
- switch from a depends on to a select for the libsndfile or
  pulseaudio or alsa dependency
- re-order statements in Config.in
- add missing host-pkgconf dependency]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>