libmisc/root_flag: add tips for --root flag only support abspath

- Add tips in error message.
- Add tips in man.
- Add zh_CN and zh_TW for tips.

Signed-off-by: Celeste Liu <coelacanthus@outlook.com>

po/ru.po

@@ -10,7 +10,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: shadow 4.1.5.1-1\n"
 "Report-Msgid-Bugs-To: pkg-shadow-devel@lists.alioth.debian.org\n"
-"POT-Creation-Date: 2022-04-27 16:54+0200\n"
+"POT-Creation-Date: 2022-07-27 22:49+0800\n"
 "PO-Revision-Date: 2017-03-05 11:14+0300\n"
 "Last-Translator: Yuri Kozlov <yuray@komyakino.ru>\n"
 "Language-Team: Russian <debian-l10n-russian@lists.debian.org>\n"
@@ -19,8 +19,8 @@ msgstr ""
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
 "X-Generator: Lokalize 2.0\n"
-"Plural-Forms:  nplurals=3; plural=(n%10==1 && n%100!=11 ? 0 : n%10>=2 && n"
-"%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2);\n"
+"Plural-Forms:  nplurals=3; plural=(n%10==1 && n%100!=11 ? 0 : n%10>=2 && "
+"n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2);\n"
 
 #, c-format
 msgid ""
@@ -557,8 +557,9 @@ msgstr "%s: для параметра «%s» требуется аргумент
 msgid "%s: failed to drop privileges (%s)\n"
 msgstr "%s: не удалось снизить уровень привилегий (%s)\n"
 
-#, c-format
-msgid "%s: invalid chroot path '%s'\n"
+#, fuzzy, c-format
+#| msgid "%s: invalid chroot path '%s'\n"
+msgid "%s: invalid chroot path '%s', only absolute paths are supported.\n"
 msgstr "%s: некорректное значение пути chroot «%s»\n"
 
 #, c-format