drm/tegra: Remove memory allocation from Falcon library

drm/tegra: Remove memory allocation from Falcon library

Having to provide allocator hooks to the Falcon library is somewhat
cumbersome and it doesn't give the users of the library a lot of
flexibility to deal with allocations. Instead, remove the notion of
Falcon "operations" and let drivers deal with the memory allocations
themselves.

Signed-off-by: Thierry Reding <treding@nvidia.com>