Fix warnings reported by dtbs_check :
arch/arm64/boot/dts/mediatek/mt8186.dtsi:1163.35-1168.5: Warning (simple_bus_reg):
/soc/mailbox@10686000: simple-bus unit address format error, expected "10686100"
arch/arm64/boot/dts/mediatek/mt8186.dtsi:1170.35-1175.5: Warning (simple_bus_reg):
/soc/mailbox@10687000: simple-bus unit address format error, expected "10687100"
by having the right bus address as node name.
Fixes: 379cf0e639ae ("arm64: dts: mediatek: mt8186: Add ADSP mailbox nodes")
Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>