Convert para_write to lopsub.

Convert para_write to lopsub.

This replaces the gengetopt file write.m4 by write.suite.m4, making use
of the shared macros in m4/lls/include for --channels, --sample-format
and --sample-rate.

The gengetopt files for these options are not needed for the unconverted
executables which still rely on gengetopt, so they can be removed.

In write.c we now use LLS_COPY_WAV_PARMS() rather than
COPY_WAV_PARMS(). The latter macro becomes unused and is removed
as well.