Introduce tst_parse_opts()

The pattern that was used in all testcases is:

const char *msg;

msg = parse_opts(...);
if (msg)
	tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

This change simplifies the steps to just calling:

tst_parse_opts(...);

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/lib/ltp_priv.h b/lib/ltp_priv.h
index 9507e9d..813df2a 100644
--- a/lib/ltp_priv.h
+++ b/lib/ltp_priv.h
@@ -47,4 +47,7 @@
 #define USC_NO_FUNC_CHECK	"USC_NO_FUNC_CHECK"
 #define USC_LOOP_DELAY		"USC_LOOP_DELAY"
 
+const char *parse_opts(int ac, char **av, const option_t *user_optarr, void
+                       (*uhf)(void));
+
 #endif /* __LTP_PRIV_H__ */