lineedit: remove ->path_lookup if ash is not configured

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 5eb701f..1a3f296 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -743,9 +743,11 @@
 	char *tmp;
 	char **res;
 
+#if EDITING_HAS_path_lookup
 	if (state->flags & WITH_PATH_LOOKUP)
 		pth = state->path_lookup;
 	else
+#endif
 		pth = getenv("PATH");
 
 	/* PATH="" or PATH=":"? */