getopt32: fix getopt32 breakage (forgot to memset(0) it) -- thanks rockeychu

diff --git a/libbb/getopt32.c b/libbb/getopt32.c
index 1071023..c7c8cb7 100644
--- a/libbb/getopt32.c
+++ b/libbb/getopt32.c
@@ -355,6 +355,7 @@
 		}
 		/* count == no. of longopts + 1 */
 		long_options = alloca(count * sizeof(*long_options));
+		memset(long_options, 0, count * sizeof(*long_options));
 		i = 0;
 		optstr = applet_long_options;
 		while (--count) {