correct the setenv option judging condition

Change-Id: I10ed6275374f572da639f26611f607bf7607905c
diff --git a/init/init_parser.c b/init/init_parser.c
index 02e5bdc..7800082 100644
--- a/init/init_parser.c
+++ b/init/init_parser.c
@@ -760,7 +760,7 @@
         break;
     case K_setenv: { /* name value */
         struct svcenvinfo *ei;
-        if (nargs < 2) {
+        if (nargs < 3) {
             parse_error(state, "setenv option requires name and value arguments\n");
             break;
         }