Fix typo and portability issue in r30555

cmr=v1.7.4:ticket=trac:4223

This commit was SVN r30559.

The following SVN revision numbers were found above:
  r30555 --> open-mpi/ompi@5c35b5ba19

The following Trac tickets were found above:
  Ticket 4223 --> https://svn.open-mpi.org/trac/ompi/ticket/4223

config/opal_setup_wrappers.m4

@@ -214,7 +214,7 @@ AC_DEFUN([OPAL_SETUP_RUNPATH],[
 # runtime), and the RUNPATH args, if we have them.
 AC_DEFUN([RPATHIFY_LDFLAGS],[
     OPAL_VAR_SCOPE_PUSH([rpath_out rpath_dir rpath_tmp])
-    AS_IF([test "$enable_wrapper_rpath" = "yes" -a ! "$WRAPPER_RPATH_SUPPORT" = "disabled" -a ! "WRAPPER_RPATH_SUPPORT" = "unnecessary"], [
+    AS_IF([test "$enable_wrapper_rpath" = "yes" && test "$WRAPPER_RPATH_SUPPORT" != "disabled" && test "$WRAPPER_RPATH_SUPPORT" != "unnecessary"], [
            rpath_out=""
            for val in ${$1}; do
                case $val in