linux-phytec-ti

arm64: dts: k3-am6: Enable PCIe GEN3 mode in RC mode

Set max-link-speed dt property to '3' in order to enable PCIe GEN3 mode
in RC mode. EP dt node already has max-link-speed set to '3'

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>