Make subdir in released tarball package always be named 'lib', and not 'lib64'

Currently, if there is /usr/lib64 in the system, where 64bit binaries are built, making both 'install' and 'package' targets put library file into lib64 folder under CMAKE_INSTALL_PREFIX or in the tarball, respectively.
I am not 100% sure that is wrong, but C/C puts files in the tarball in 'lib' subdirectory, and c/odbc should be at least in line with c/c in that. Plus, if package c/c plugins, that creates both 'lib' and 'lib64' folders in the tarball.