staging: android: add SPDX identifiers to all android driver files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the android driver files with the correct SPDX license identifier
based on the license text in the file itself.  The SPDX identifier is a
legally binding shorthand, which can be used instead of the full boiler
plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: "Arve Hjønnevåg" <arve@android.com>
Cc: Riley Andrews <riandrews@android.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ashmem.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* mm/ashmem.c
  *
  * Anonymous Shared Memory Subsystem, ashmem

drivers/staging/android/ashmem.h

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: (GPL-2.0 OR Apache-2.0)
 /*
  * include/linux/ashmem.h
  *

drivers/staging/android/ion/ion-ioctl.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *
  * Copyright (C) 2011 Google, Inc.

drivers/staging/android/ion/ion.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *
  * drivers/staging/android/ion/ion.c

drivers/staging/android/ion/ion.h

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion.h
  *

drivers/staging/android/ion/ion_carveout_heap.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_carveout_heap.c
  *

drivers/staging/android/ion/ion_chunk_heap.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_chunk_heap.c
  *

drivers/staging/android/ion/ion_cma_heap.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_cma_heap.c
  *

drivers/staging/android/ion/ion_heap.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_heap.c
  *

drivers/staging/android/ion/ion_page_pool.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_mem_pool.c
  *

drivers/staging/android/ion/ion_system_heap.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/ion/ion_system_heap.c
  *

drivers/staging/android/uapi/ashmem.h

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: (GPL-2.0 OR Apache-2.0)
 /*
  * drivers/staging/android/uapi/ashmem.h
  *

drivers/staging/android/uapi/ion.h

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/staging/android/uapi/ion.h
  *