fix memleak at lib/utilunix.c:my_systemv_flags()

[and]

fix memleak at lib/utilunix.c:my_systemv_flags()

array contents point to dynamically-allocated memory (e.g. g_strdup)
must freed explicit, g_ptr_array_free() is not enough.

call _all_ g_ptr_array_add() with g_strdup() so we can easily
use g_ptr_array_foreach() with g_free() on each array element.

found by LeakSanitizer?

Direct leak of 8 byte(s) in 1 object(s) allocated from:

#0 0x4d5d62 in malloc (/tmp/portage/app-misc/mc-9999/work/mc-9999/src/mc+0x4d5d62)
#1 0x7ff2e7a967d4 in g_malloc (/usr/lib64/libglib-2.0.so.0+0x677d4)
#2 0x7ff2e7abd111 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x8e111)
#3 0x64514a in my_system_make_arg_array /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/utilunix.c:218:38
#4 0x644877 in my_systemv_flags /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/utilunix.c:485:18
#5 0x6446fb in my_systeml /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/utilunix.c:414:14
#6 0x67fbde in sfs_vfmake /tmp/portage/app-misc/mc-9999/work/mc-9999/src/vfs/sfs/sfs.c:209:9
#7 0x67ee40 in sfs_redirect /tmp/portage/app-misc/mc-9999/work/mc-9999/src/vfs/sfs/sfs.c:247:9
#8 0x67e6f4 in sfs_open /tmp/portage/app-misc/mc-9999/work/mc-9999/src/vfs/sfs/sfs.c:273:16
#9 0x57a4a0 in mc_open /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/interface.c:209:16
#10 0x681b33 in tar_open_archive_int /tmp/portage/app-misc/mc-9999/work/mc-9999/src/vfs/tar/tar.c:315:18
#11 0x6803f5 in tar_open_archive /tmp/portage/app-misc/mc-9999/work/mc-9999/src/vfs/tar/tar.c:761:12
#12 0x695eb3 in vfs_s_get_path /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/direntry.c:1150:18
#13 0x6a2dc7 in vfs_s_inode_from_path /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/direntry.c:380:9
#14 0x69e20d in vfs_s_opendir /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/direntry.c:409:11
#15 0x69f178 in vfs_s_chdir /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/direntry.c:477:12
#16 0x5818ea in mc_chdir /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/vfs/interface.c:684:16
#17 0x5b8e4c in _do_panel_cd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/panel.c:3223:9
#18 0x5b8c81 in do_panel_cd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/panel.c:4588:9
#19 0x5bd055 in do_cd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/panel.c:4987:11
#20 0x5353f1 in exec_extension_cd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/ext.c:400:5
#21 0x534264 in exec_extension /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/ext.c:436:9
#22 0x533527 in regex_command_for /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/ext.c:1029:34
#23 0x5c7d5b in do_enter_on_file_entry /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/panel.c:2748:9
#24 0x5cda2a in panel_execute_cmd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/panel.c:3399:9
#25 0x52fc94 in dlg_key_event /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:515:19
#26 0x530546 in frontend_dlg_run /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:570:9
#27 0x530165 in dlg_run /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:1267:5
#28 0x5a1f4a in do_nc /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/midnight.c:1762:9
#29 0x4fa3e8 in main /tmp/portage/app-misc/mc-9999/work/mc-9999/src/main.c:418:21

Signed-off-by: Andreas Mohr <and@…>

[andrew_b]

Thanks!
Fixed without string duplication: [a382b1558bef403d6fdc7d1c4dd360b1f7deca4a].