platform/x86: mlx-platform: fix module aliases

Missing prefix 'pn' in MODULE_ALIAS lines causes the module to
not load automatically. The driver should use MODULE_DEVICE_TABLE
together with existing mlxplat_dmi_table instead.

Fixes: 6613d18e

 ("platform/x86: mlx-platform: Move module from arch/x86")
Cc: Vadim Pasternak <vadimp@mellanox.com>
Cc: Bjørn Mork <bjorn@mork.no>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>