LU-13107 utils: remove duplicate lctl erase/fork_lcfg

LU-13107 utils: remove duplicate lctl erase/fork_lcfg

A patch merge error resulted in duplicate erase_lcfg and fork_lcfg
sub-commands in lctl.  Remove the duplicates, and move them to the
llog section, since they relate to the configuration llogs.

Fixes: b0efebdaef52 ("LU-13107 utils: clean up lctl command usage")
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I4449f7dbb0ab7b643e5057131bbc9620ac457a3d
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/48886
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Timothy Day <timday@amazon.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>