Memory leak when reconnecting fails

Hey Georg,

unfortunately the CONC-118 is not completely fixed in Rev. 192. There is still memory-leak if the reconnecting fails.

How to reproduce:

Step 1. Build the test code
Step 2. Start MySQL/Mariadb server
Step 3. Execute the test binary (in terminal or valgrind), and it would keep printing "Query OK"..
Step 4. Shut down MySQL/Mariadb server. And the client would keep printing "Query error..."
Step 5. Watch the memory usage of the test binary, and it would keep raising.

Solution:
Delete line 2025 in file libmariadb.c from rev.192. ( a bzero function )

And my last comment in CONC-118 explains why.

PS:
There is a patch from me when I reported the bug CONC118, which has already deleted the "bzero" line. Perhaps you have missed this point.

Best Regards
Tianhong