drm/lima: Mark simple_ondemand governor as softdep

drm/lima: Mark simple_ondemand governor as softdep

Lima DRM driver uses devfreq to perform DVFS, while using simple_ondemand
devfreq governor by default.  This causes driver initialization to fail on
boot when simple_ondemand governor isn't built into the kernel statically,
as a result of the missing module dependency and, consequently, the
required governor module not being included in the initial ramdisk.  Thus,
let's mark simple_ondemand governor as a softdep for Lima, to have its
kernel module included in the initial ramdisk.

This is a rather longstanding issue that has forced distributions to build
devfreq governors statically into their kernels, [1][2] or may have forced
some users to introduce unnecessary workarounds.

Having simple_ondemand marked as a softdep for Lima may not resolve this
issue for all Linux distributions.  In particular, it will remain
unresolved for the distributions whose utilities for the initial ramdisk
generation do not handle the available softdep information [3] properly
yet.  However, some Linux distributions already handle softdeps properly
while generating their initial ramdisks, [4] and this is a prerequisite
step in the right direction for the distributions that don't handle them
properly yet.

[1] https://gitlab.manjaro.org/manjaro-arm/packages/core/linux-pinephone/-/blob/6.7-megi/config?ref_type=heads#L5749
[2] https://gitlab.com/postmarketOS/pmaports/-/blob/7f64e287e7732c9eaa029653e73ca3d4ba1c8598/main/linux-postmarketos-allwinner/config-postmarketos-allwinner.aarch64#L4654
[3] https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/commit/?id=49d8e0b59052999de577ab732b719cfbeb89504d
[4] https://github.com/archlinux/mkinitcpio/commit/97ac4d37aae084a050be512f6d8f4489054668ad

Cc: Philip Muller <philm@manjaro.org>
Cc: Oliver Smith <ollieparanoid@postmarketos.org>
Cc: Daniel Smith <danct12@disroot.org>
Cc: stable@vger.kernel.org
Fixes: 1996970773a3 ("drm/lima: Add optional devfreq and cooling device support")
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/fdaf2e41bb6a0c5118ff9cc21f4f62583208d885.1718655070.git.dsimic@manjaro.org