[PATCH 2/4] OvmfPkg/License.txt: refresh the MIT license text and include the SPDX ID

["Laszlo Ersek" <lersek@redhat.com>]

Refresh the MIT license text from <https://spdx.org/licenses/MIT.html>,
and add "SPDX-License-Identifier: MIT" for easier parsing by machines.

This follows the tree-wide adoption of "SPDX-License-Identifier"s, made
for <https://bugzilla.tianocore.org/show_bug.cgi?id=1373>; in particular:

- commit 304bff7223a8 ("edk2: Change License.txt from 2-Clause BSD to
  BSD+Patent", 2019-04-09),

- commit 75fae505b735 ("OvmfPkg: Change License.txt from 2-Clause BSD to
  BSD+Patent", 2019-04-09).

Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Julien Grall <julien.grall@arm.com>
Cc: Lars Kurth <lars.kurth@citrix.com>
Cc: xen-devel@lists.xenproject.org
Bugzilla: https://bugzilla.tianocore.org/show_bug.cgi?id=1654
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---
 OvmfPkg/License.txt | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/OvmfPkg/License.txt b/OvmfPkg/License.txt
index a2e02a1796aa..6ec950cd9e13 100644
--- a/OvmfPkg/License.txt
+++ b/OvmfPkg/License.txt
@@ -55,19 +55,22 @@ POSSIBILITY OF SUCH DAMAGE.
 Some files are subject to the following license, the MIT license. Those files
 are located in:
 - OvmfPkg/Include/IndustryStandard/Xen/
 - OvmfPkg/XenBusDxe/
 
+SPDX-License-Identifier: MIT
+
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
-The above copyright notice and this permission notice shall be included in
-all copies or substantial portions of the Software.
+The above copyright notice and this permission notice (including the next
+paragraph) shall be included in all copies or substantial portions of the
+Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-- 
2.19.1.3.g30247aa5d201