habanalabs: Avoid double free in error flow

In case kernel context init fails during device initialization, both
hl_ctx_put() and kfree() are called, ending with a double free of the
kernel context.
Calling kfree() is needed only when a failure happens between the
allocation of the kernel context and its initialization, so move it to
there and remove it from the error flow.

Signed-off-by: Tomer Tayar <ttayar@habana.ai>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>