Port of a Linux commit 8cfab3c

  Add SPDX GPL-2.0 to all PCI files that specified the GPL version 2 license.

  Remove the boilerplate GPL version 2 language, relying on the assertion in
  b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to
  files with no license") that the SPDX identifier may be used instead of the
  full boilerplate text.

  Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
  Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>