drivers/pci.lua: add kmod-mt7615-firmware into Mediatek MT7615
This card requires firmware to be loaded and this firmware is in package
kmod-mt7615-firmware
[1].
Fixes:
Mar 9 18:38:45 turris procd: Could not find firmware /lib/firmware/mediatek/mt7615_rom_patch.bin: No such file or directory
[1] https://github.com/openwrt/openwrt/commit/479f1f2c92f6b7e75f945cfdb2214b609a92b692
This is only reuqired to Turris OS 6.0 or newer versions.
Edited by Josef Schlehofer