dt-bindings: serial: 8250: add aspeed, lpc-io-reg and aspeed, lpc-interrupts

dt-bindings: serial: 8250: add aspeed, lpc-io-reg and aspeed, lpc-interrupts

These correspond to the existing lpc_address, sirq, and sirq_polarity
sysfs attributes; the second element of aspeed,lpc-interrupts provides
a replacement for the deprecated aspeed,sirq-polarity-sense property.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210412034712.16778-5-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>