CRIS: Fix bugs in return value of atomic_inc_return and atomic_dec_return.

Increment and decrement before assigning to return value.
diff --git a/include/asm-cris/atomic.h b/include/asm-cris/atomic.h
index 2949a94..5fc8776 100644
--- a/include/asm-cris/atomic.h
+++ b/include/asm-cris/atomic.h
@@ -91,7 +91,7 @@
 	unsigned long flags;
 	int retval;
 	cris_atomic_save(v, flags);
-	retval = (v->counter)++;
+	retval = ++(v->counter);
 	cris_atomic_restore(v, flags);
 	return retval;
 }
@@ -101,7 +101,7 @@
 	unsigned long flags;
 	int retval;
 	cris_atomic_save(v, flags);
-	retval = (v->counter)--;
+	retval = --(v->counter);
 	cris_atomic_restore(v, flags);
 	return retval;
 }