LICENSES: Add Linux-OpenIB license text

The infiniband code uses a variant of the OpenIB license. This license is
BSD-2-Clause with the MIT disclaimer. The linux kernel uses this license
extensively throughout the driver subsystem since 2005. Note that the
OpenIB.org license is a true match to BSD-2-Clause.

The license text was copied from:

    https://spdx.org/licenses/Linux-OpenIB.html#licenseText

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

LICENSES/other/Linux-OpenIB

@@ -0,0 +1,26 @@
+Valid-License-Identifier: Linux-OpenIB
+SPDX-URL: https://spdx.org/licenses/Linux-OpenIB.html
+Usage-Guide:
+  To use the Linux Kernel Variant of OpenIB.org license put the following
+  SPDX tag/value pair into a comment according to the placement guidelines
+  in the licensing rules documentation:
+    SPDX-License-Identifier: Linux-OpenIB
+License-Text:
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    - Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    - Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+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
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.