lib: Remove unnecessary parentheses

The freebsd compiler complains that there is an extra set of ()'s
around the if statement.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
diff --git a/lib/vty.c b/lib/vty.c
index ff013cf..3891661 100644
--- a/lib/vty.c
+++ b/lib/vty.c
@@ -425,7 +425,7 @@
       snprintf(vty_str, sizeof(vty_str), "vty[??]@%s", vty->address);
       if (vty)
         for (i = 0; i < vector_active (vtyvec); i++)
-          if ((vty == vector_slot (vtyvec, i)))
+          if (vty == vector_slot (vtyvec, i))
             {
               snprintf(vty_str, sizeof(vty_str), "vty[%d]@%s",
                                                  i, vty->address);