Update license clause to reflect actual licensing

Update spec file license to reflect current state

Several parts of libnvidia-container (and dependencies) are not BSD-licensed, or are ambiguously-licensed.  This updates the spec file to reflect current state, including some comments so the reasoning isn't lost.  If NVIDIA#74 is resolved, this may change. :)

* elftoolchain is licensed under BSD-3-Clause
  https://github.com/elftoolchain/elftoolchain#copyright-and-license
* libnvidia-container is licensed under apache-2.0
  https://github.com/NVIDIA/libnvidia-container/blob/master/LICENSE
* libnvidia-container includes the GLPv3 license
  https://github.com/NVIDIA/libnvidia-container/blob/master/COPYING
* libnvidia-container includes the LGPLv3 license
  https://github.com/NVIDIA/libnvidia-container/blob/master/COPYING.LESSER
* nvidia-modprobe is licensed under GPLv2
  https://github.com/NVIDIA/nvidia-modprobe/blob/master/COPYING
* several (14) nvidia-modprobe files contain the MIT license header
  https://github.com/NVIDIA/nvidia-modprobe/blob/master/utils.mk

pkg/rpm/SPECS/libnvidia-container.spec

@@ -1,5 +1,17 @@
 Name: libnvidia-container
-License: BSD
+License:        BSD-3-Clause AND Apache-2.0 AND GPL-3.0-or-later AND LGPL-3.0-or-later AND MIT AND GPL-2.0-only
+# elftoolchain is licensed under BSD-3-Clause
+#  https://github.com/elftoolchain/elftoolchain#copyright-and-license
+# libnvidia-container is licensed under apache-2.0
+#  https://github.com/NVIDIA/libnvidia-container/blob/master/LICENSE
+# libnvidia-container includes the GLPv3 license
+#  https://github.com/NVIDIA/libnvidia-container/blob/master/COPYING
+# libnvidia-container includes the LGPLv3 license
+#  https://github.com/NVIDIA/libnvidia-container/blob/master/COPYING.LESSER
+# nvidia-modprobe is licensed under GPLv2
+#  https://github.com/NVIDIA/nvidia-modprobe/blob/master/COPYING
+# several nvidia-modprobe files contain the MIT license header
+#  https://github.com/NVIDIA/nvidia-modprobe/blob/master/utils.mk
 Vendor: NVIDIA CORPORATION
 Packager: NVIDIA CORPORATION <cudatools@nvidia.com>
 URL: https://github.com/NVIDIA/libnvidia-container