Fix typo in the new v2 license

Signed-off-by: NMiguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: NCosmin Truta <ctruta@gmail.com>

LICENSE

@@ -13,7 +13,7 @@ PNG Reference Library License version 2
 The software is supplied "as is", without warranty of any kind,
 express or implied, including, without limitation, the warranties
 of merchantability, fitness for a particular purpose, title, and
-non-infringement.  In no even shall the Copyright owners, or
+non-infringement.  In no event shall the Copyright owners, or
 anyone distributing the software, be liable for any damages or
 other liability, whether in contract, tort or otherwise, arising
 from, out of, or in connection with the software, or the use or

png.h

@@ -35,7 +35,7 @@
  * The software is supplied "as is", without warranty of any kind,
  * express or implied, including, without limitation, the warranties
  * of merchantability, fitness for a particular purpose, title, and
- * non-infringement.  In no even shall the Copyright owners, or
+ * non-infringement.  In no event shall the Copyright owners, or
  * anyone distributing the software, be liable for any damages or
  * other liability, whether in contract, tort or otherwise, arising
  * from, out of, or in connection with the software, or the use or