libsemanage: fix deprecation warning for bison

The %name-prefix="foo" syntax was deprecated in bison 2.3b [1], which
was released in 2006. This patches fixes the syntax to use the newer
syntax. This breaks support for older versions of bison.

[1] http://lists.gnu.org/archive/html/help-bison/2009-10/msg00018.html

Reported-by: Ilya Frolov <ilya.a.frolov@gmail.com>
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
diff --git a/libsemanage/src/conf-parse.y b/libsemanage/src/conf-parse.y
index 80d08ec..7061d8a 100644
--- a/libsemanage/src/conf-parse.y
+++ b/libsemanage/src/conf-parse.y
@@ -50,7 +50,7 @@
 
 %}
 
-%name-prefix="semanage_"
+%name-prefix "semanage_"
 
 %union {
         int d;