LinuxKPI: Add PCI method for transferring framebuffer parameters

[wulf]

Summary

from LKPI video driver to FreeBSD native framebuffer driver.
This makes possible to attach framebuffer driver in traditional way
using newbus interface rather than direct calls into vt internals.
It is required to make LKPI framebuffer driver compatible with
fbd/vt_fb. As a consequence that allows us to switch back to vt_fb on
radeon driver where vt_drmfb regressions have been reported [1].

The method expects fbd device ivars pointed to FreeBSD fb_info
structure embedded in to Linux fb_info structure. See linux/fb.h.
Note that some out-of-tree non-PCI drm drivers may require similar
changes in parent bus drivers.

[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=285088

PR: 285088

[bz]

sys/compat/linuxkpi/common/src/linux_pci.c

2471

I think you need a pdev->pdrv != NULL check here too, so:

if (pdev->pdrv == NULL || !pdev->pdrv->isdrm)

[wulf]

pdev->pdrv == NULL check added.