run-command: fix return value comment

483bbd4 (run-command: introduce child_process_init(), 2014-08-19) and
2d71608 (run-command: factor out child_process_clear(), 2015-10-24)
added help texts about child_process_init() and child_process_clear()
without updating the immediately following documentation of return codes
that only applied to the preexisting functions.

4c4066d (run-command: move doc to run-command.h, 2019-11-17) started
to list the functions explicitly that this paragraph applies to, but
still wrongly included child_process_init() and child_process_clear().
Remove their names from that list.

Suggested-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: René Scharfe <[email protected]>
Signed-off-by: Taylor Blau <[email protected]>

Author: rscharfe

run-command.h

@@ -150,9 +150,8 @@ struct child_process {
 }
 
 /**
- * The functions: child_process_init, start_command, finish_command,
- * run_command, run_command_v_opt, run_command_v_opt_cd_env, child_process_clear
- * do the following:
+ * The functions: start_command, finish_command, run_command,
+ * run_command_v_opt, run_command_v_opt_cd_env do the following:
  *
  * - If a system call failed, errno is set and -1 is returned. A diagnostic
  *   is printed.