On one of my Redhat 6.2 installations the libraries for mysql
are located in /usr/lib/mysql these being:-

libdbug.a    libmerge.a    libmysqlclient.la
libmsys.a    libheap.a     libmysqlclient.a
libmystrings.a    libnisam.a
[download]

If you can find these on your system then use this location
in the Makefile.
Hope this helps