sgsnemu: Fix gengetopt package name

gengetopt by default picks the program name from PACKAGE (autotools),
which is osmo-ggsn and is obviously wrong in case of sgsnemu.

After this patch, "sgsnemu --help" no longer shows "osmo-ggsn" but
"sgsnemu" at the top of the help text.

Change-Id: Ifabc2435a503ef71aa5a002ca46833f329068b37
diff --git a/sgsnemu/cmdline.ggo b/sgsnemu/cmdline.ggo
index 0184775..4fcc64a 100644
--- a/sgsnemu/cmdline.ggo
+++ b/sgsnemu/cmdline.ggo
@@ -13,6 +13,8 @@
 # 	sed -i -e 's/int qose1_arg;/unsigned long long int qose1_arg;/' cmdline.h
 # to generate cmdline.c and cmdline.h
 
+package "sgsnemu"
+
 option  "debug"        d "Run in debug mode"              flag   off
 
 option  "conf"         c "Read configuration file"        string no