Scatter/gather was introduced in 6.2 kernel and caused flickering
and various issues when running iGPU on Ryzen 7000-series CPUs.
This issue is not observed in kernel 6.6 or newer versions
so we can enable it for kernel 6.6 and newer versions.
Change condition to check actually used kernel version instead of which kernel version is the default.
Without this change, if a user changes the kernel version to a newer version, the kernel parameter will not actually be added.