net/qla3xxx: Convert to SPDX license identifiers

All files related to this driver contain the following notice:

  See LICENSE.qla3xxx for copyright and licensing details.

LICENSE.qla3xxx can be found in
Documentation/networking/device_drivers/qlogic/. The file contains:

  - A copyright notice

    This copyright notice is redundant as all files contain the same
    copyright notice already

  - A license notice

    You may modify and redistribute the device driver code under the GNU
    General Public License (a copy of which is attached hereto as Exhibit
    A) published by the Free Software Foundation (version 2 or a later
    version).

    This can be replaced with the corresponding SPDX license identifier
    (GPL-2.0-or-later) in the source files which reference this license
    file.

  - A license for the device firmware

    This license is pointless in the context of the kernel as the firmware
    is not distributed as part of the kernel.

    LICENSE.qla2xxx contained exactly the same firmware license which was
    removed with commit bc3f957c

 ("[SCSI] qla2xxx: Update
    LICENSE.qla2xxx.").

    The firmware license is there due to the fact that the out of tree
    driver tarball which was available from the qlogic website contained
    the firmware binary. The firmware license in the qla3xxx license file
    got probably forgotten when the other qlogic license files were
    updated.

Remove the notices and add the SPDX license identifier GPL-2.0-or-later to
the source files.

Finally remove the now redundant LICENSE.qla3xxx file.

Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>