Fix broken modinfo.

From upstream: http://busybox.net/downloads/fixes-1.23.1/busybox-1.23.1-modinfo.patch

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>

--- busybox-1.23.1/modutils/modinfo.c
+++ busybox-1.23.1-modinfo/modutils/modinfo.c
@@ -154,7 +154,7 @@ int modinfo_main(int argc UNUSED_PARAM,
 		if (colon == NULL)
 			continue;
 		*colon = '\0';
-		filename2modname(tokens[0], name);
+		filename2modname(bb_basename(tokens[0]), name);
 		for (i = 0; argv[i]; i++) {
 			if (fnmatch(argv[i], name, 0) == 0) {
 				modinfo(tokens[0], uts.release, &env);