[license] Update the text in LICENSE to refer to PATENTS

Change-Id: Ia895d5758d463e357d2da2fe9c77cd5fcda6cd34

LICENSE

@@ -1,9 +1,16 @@
-The Magenta Kernel (kernel/...) is under the MIT License, a copy of which
+The Magenta Kernel (kernel/...) and the Magenta Scripts (scripts/...)
-may be found in kernel/LICENSE
+are under an MIT-style license, copies of which may be found in
+kernel/LICENSE and scripts/LICENSE.
 
-The Magenta System (system/...) and Bootloader (bootloader/...) are under the
+The Third Party Components (third_party/...) are under various
-BSD License, a copy of which may be found in system/LICENSE
+licenses (of the BSD, MIT, or Zlib style), which may be found in the
+root directory of each component, respectively.
 
-The Third Party Components (third_party/...) are under various licenses
+All other components and materials, including the Magenta System
-(of the BSD, MIT, or Zlib style), which may be found in the root directory
+(system/...) and Bootloader (bootloader/...), are under a BSD-style
-of each component, respectively.
+license, copies of which may be found in system/LICENSE and
+bootloader/LICENSE.
+
+The PATENTS file, which may be found in the same directories as the
+LICENSE files, provides additional license rights and conditions
+relating to patents.