reset: tegra-bpmp: allow building under COMPILE_TEST

The Tegra BPMP reset driver can be compiled without TEGRA_BPMP being
enabled. Allow it to be built under COMPILE_TEST.

Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20240625-reset-compile-bpmp-v1-1-647e846303d8@pengutronix.de


Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>