do not enable the use of openmp in simgrid mode

configure.ac

@@ -2813,10 +2813,12 @@ fi
 AM_CONDITIONAL([STARPU_OPENMP], [test "x$enable_openmp" = "xyes"])
 AC_MSG_RESULT($enable_openmp)
 
-AM_CONDITIONAL([STARPU_HAVE_OPENMP],[test -n "$OPENMP_CFLAGS"])
-if test -n "{OPENMP_CFLAGS}"; then
-   CFLAGS="${CFLAGS} ${OPENMP_CFLAGS}"
-   STARPU_OMP_LDFLAGS="${OPENMP_CFLAGS}"
+if test x$enable_simgrid = xno; then
+  AM_CONDITIONAL([STARPU_HAVE_OPENMP],[test -n "$OPENMP_CFLAGS"])
+  if test -n "{OPENMP_CFLAGS}"; then
+     CFLAGS="${CFLAGS} ${OPENMP_CFLAGS}"
+     STARPU_OMP_LDFLAGS="${OPENMP_CFLAGS}"
+  fi
 fi
 
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