Bump to 2.4.15 for release.
diff --git a/configure.ac b/configure.ac
index 9832caf..870c056 100644
--- a/configure.ac
+++ b/configure.ac
@@ -19,7 +19,7 @@
 #  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 AC_PREREQ(2.60)
-AC_INIT([libdrm], 2.4.14, [dri-devel@lists.sourceforge.net], libdrm)
+AC_INIT([libdrm], 2.4.15, [dri-devel@lists.sourceforge.net], libdrm)
 AC_USE_SYSTEM_EXTENSIONS
 AC_CONFIG_SRCDIR([Makefile.am])
 AM_INIT_AUTOMAKE([dist-bzip2])