Move initialization of cmd->fmt into init_formats().

Move initialization of cmd->fmt into init_formats().

init_formats() sets up the command formats, and currently sets cmd->fmt_backup
but does not set cmd->fmt to a default value.  This seems incorrect so we
set it to cmd->default_settings.fmt before returning.

The call we remove here may set cmd->fmt based on a command line setting.
But it is safe to remove this, because the only caller of init_lvm() that
cares about the cmdline override is the cmdline tools (clvmd does not care),
called from lvm2_main().  After lvm2_main() calls init_lvm(), it later calls
lvm_run_command().  In lvm_run_command(), we have a call to _apply_settings(),
which has the identical assignment of cmd->fmt that this patch removes.