Use ASPM_MASK_NEG instead of hard-coded value, as other callers of
rtsx_pci_update_cfg_byte() do.  No functional change intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20200521180545.1159896-4-helgaas@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>