fix a typo on the website

git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@327237 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/www/index.html b/www/index.html
index ff982cb..56df855 100644
--- a/www/index.html
+++ b/www/index.html
@@ -147,7 +147,7 @@
     Ports to other architectures and operating systems are welcome.
   </p>
 
-  <p>A full OS and archiecture compatibility matrix is in
+  <p>A full OS and architecture compatibility matrix is in
     <a href="README.txt">README.txt</a>
   </p>