ash,hush: handle a few more bkslash-newline cases

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/hush_test/hush-parsing/bkslash_newline2.right b/shell/hush_test/hush-parsing/bkslash_newline2.right
new file mode 100644
index 0000000..c863c54
--- /dev/null
+++ b/shell/hush_test/hush-parsing/bkslash_newline2.right
@@ -0,0 +1,4 @@
+Line with one backslash:
+\
+
+Ok:0