drm/amdgpu/psp: deallocate memory when psp_load_fw failed

psp_load_fw failure would cause memory leak for psp tmr and psp ring
because psp_hw_init is not called as psp block is not fully initialized.
Clean up psp tmr and psp ring when psp_load_fw fail by calling
psp_free_shared_bufs and psp_ring_destroy.

Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alice Wong <shiwei.wong@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>