fcitx-pinyin should be automatically replaced by fcitx-chinese-addons

Currently pkg_add -u doesn't touch fcitx-pinyin and there is no prompt
reminding users to use the new package.

When upgrading fcitx from 4 to 5, the old fcitx-pinyin package should
be replaced by fcitx-chinese-addons, which is the new package offering
pinyin support.

Here is a diff attempting to fix it by adding a line to Quirks.pm, is
this the correct approach?

diff --git a/devel/quirks/files/Quirks.pm b/devel/quirks/files/Quirks.pm
index 62fb724b4df..4eeb920adb2 100644
--- a/devel/quirks/files/Quirks.pm
+++ b/devel/quirks/files/Quirks.pm
@@ -726,6 +726,7 @@ my $stem_extensions = {
'libgweather' => 'libgweather4',
'spidermonkey78' => 'spidermonkey91',
'gmime' => 'gmime30',
+ 'fcitx-pinyin' => 'fcitx-chinese-addons',
};

my $obsolete_reason = {};