CONFIG_ARCH_MEDIATEK is not available for the selected architecture x86.
Result is shown for architecture arm

MediaTek SoC Support

modulename: irq-mtk-sysirq.ko

configname: CONFIG_ARCH_MEDIATEK

Linux Kernel Configuration
└─>MediaTek SoC Support
In linux kernel since version 3.10 (release Date: 2013-06-30)
Support for Mediatek MT65xx & MT81xx SoCs
source code: