drm/module-setup.sh: radeon needs amdkfd

drm/module-setup.sh: radeon needs amdkfd

AMD's HSA Linux kernel driver (amdkfd) has been merged into the mainline
kernel since kernel 3.19.

However, for the driver to work, it needs to be included in the default
initramfs image, together with the amd_iommu_v2 driver.

The radeon driver (AMD's kernel graphic driver) calls amdkfd during its
initialization and probing stages. Because radeon is included in the
initramfs image, it tries to initialize amdkfd during the early boot
stages. However, as amdkfd is not present there, it fails.

That doesn't harm radeon operation. However, it disables the HSA
abilities in the machine.

Because of the current design, if you later try to "modprobe amdkfd",
you won't be able to run HSA applications, even though the driver will
be loaded.

https://bugzilla.redhat.com/show_bug.cgi?id=1205222