drm/radeon: Remove unused radeon_fence_wait_any

radeon_fence_wait_any() last use was removed in 2023's
commit 254986e3 ("drm/radeon: Use the drm suballocation manager
implementation.")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>