feed_queue: rename routines for submission of a single sample value

feed_queue: rename routines for submission of a single sample value

Common feed queue support originated from input module RLE compression.
Its API would accept a single sample value and optionally repeat that
value several times.

Rename the routines and its parameter for improved awareness. Adjust
existing callers: The asix-omega, atorch, kingst-la, rdtech-tc, and
rdtech-um acquisition device drivers, as well as the protocoldata,
stf, and vcd input modules.

See a word diff for the essence of the change.