drm: fix leaked dma handles after removing drm_pci_free

After removing drm_pci_alloc/free, some instances where drm_pci_free()
would have kfreed the dma handle were skipped.

Ensure these handles are freed properly.

Signed-off-by: Joseph Kogut <joseph.kogut@gmail.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210518212859.4148903-1-joseph.kogut@gmail.com