tbf/test: Fix IMSI creation

Currently the generated IMSI contains blanks due to a missing '0'
flag in the corresponding snprintf statement. In addition, the buffer
is effectively limited to 15 bytes which is shorter than the
generated character sequence, such that the last character of the
IMSI is removed.

This patch fixes both issues. Since snprintf itself will add a
terminating \0 character, the whole buffer can be passed to snprintf.

Sponsored-by: On-Waves ehf
diff --git a/tests/tbf/TbfTest.cpp b/tests/tbf/TbfTest.cpp
index bdae443..bf49dbd 100644
--- a/tests/tbf/TbfTest.cpp
+++ b/tests/tbf/TbfTest.cpp
@@ -328,7 +328,7 @@
 		char imsi[16] = {0};
 		unsigned delay_csec = 1000;
 
-		snprintf(imsi, sizeof(imsi)-1, "001001%9d", i);
+		snprintf(imsi, sizeof(imsi), "001001%09d", i);
 
 		rc = gprs_rlcmac_dl_tbf::handle(bts, tlli, 0, imsi, ms_class,
 			delay_csec, buf, sizeof(buf));