mesa: Add "OR COPYRIGHT HOLDERS" to license text disclaiming liability.

This brings the license text in line with the MIT License as published
on the Open Source Initiative website:

http://opensource.org/licenses/mit-license.php

Generated automatically be the following shell command:
$ git grep 'THE AUTHORS BE LIABLE' | sed 's/:.*$//g' | xargs -I '{}' \
  sed -i 's/THE AUTHORS/THE AUTHORS OR COPYRIGHT HOLDERS/' {}

This introduces some wrapping issues, to be fixed in the next commit.

Reviewed-by: Brian Paul <brianp@vmware.com>

include/GL/osmesa.h

@@ -17,7 +17,7 @@
  * 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 BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * 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.
  */