[patch] fix memleak at filemanager/find.c:find_file()

[and]

fix memleak at filemanager/find.c:find_file()

find_parameter() allocate start_dir but object will never freed
testcase: search file

(found by LeakSanitizer?)

==8535==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 5 byte(s) in 1 object(s) allocated from:
    #0 0x4d6082 in malloc (/tmp/portage/app-misc/mc-9999/work/mc-9999/src/mc+0x4d6082)
    #1 0x7fd602feb7d4 in g_malloc (/usr/lib64/libglib-2.0.so.0+0x677d4)
    #2 0x7fd603012111 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x8e111)
    #3 0x7d4355 in find_parameters /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/find.c:763:30
    #4 0x7d2920 in find_file /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/find.c:1770:12
    #5 0x5a692e in midnight_execute_cmd /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/midnight.c:1210:9
    #6 0x5a27a4 in midnight_callback /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/midnight.c:1560:21
    #7 0x52ffce in dlg_key_event /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:520:19
    #8 0x530866 in frontend_dlg_run /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:571:9
    #9 0x530485 in dlg_run /tmp/portage/app-misc/mc-9999/work/mc-9999/lib/widget/dialog.c:1268:5
    #10 0x5a1fea in do_nc /tmp/portage/app-misc/mc-9999/work/mc-9999/src/filemanager/midnight.c:1763:9
    #11 0x4fa708 in main /tmp/portage/app-misc/mc-9999/work/mc-9999/src/main.c:418:21
    #12 0x7fd601e62133 in __libc_start_main (/lib64/libc.so.6+0x20133)
    #13 0x44f0b6 in _start (/tmp/portage/app-misc/mc-9999/work/mc-9999/src/mc+0x44f0b6)

Signed-off-by: Andreas Mohr <and@gmx.li>

[andrew_b]

Thanks!
Applied as [39fec422c2621b912168d0808c10e623b3511e74].