main: fix help missing newline

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>

diff -Nuar --exclude '*~' omnisync-1.0.orig/main.c omnisync-1.0/main.c
--- omnisync-1.0.orig/main.c	2009-01-02 01:03:20.000000000 -0800
+++ omnisync-1.0/main.c	2018-06-01 14:31:25.720686155 -0700
@@ -139,7 +139,7 @@
 	printf("-c x   community (snmp only)\n");
 	printf("-h x   host to connect to\n");
 	printf("-u x   ntpd shared memory unit\n");
-	printf("-z x   do an initial step, to speed up syncing, parameter is number of samples");
+	printf("-z x   do an initial step, to speed up syncing, parameter is number of samples\n");
 	printf("-S x   write measurements to file x\n");
 	printf("-n     do NOT submit to NTPd/set clock, query only (use in combination with -v and -f)\n");
 	printf("-f     do not fork\n");