dt-bindings: interrupt-controller: Fix typos in loongson,liointc.yaml

Fix the following typos in loongson,liointc.yaml:
children -> child
fron -> from
connected -> connect
it's -> its

Fixes: b6280c8b ("dt-bindings: interrupt-controller: Add Loongson LIOINTC")
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/r/1594869390-21053-9-git-send-email-yangtiezhu@loongson.cn


Signed-off-by: Rob Herring <robh@kernel.org>