configure: Reduce the dynamic linker path size
configure: Reduce the dynamic linker path size

gdb has a SO_NAME_MAX_PATH_SIZE of 512, so we use that as the path
size.

Fixes: #6494

Signed-off-by: Rafael Ávila de Espíndola <1975039f9046bf513b77c0c5639a0efc25f00e7f@scylladb.com>
Message-Id: <20200528202741.398695-2-1975039f9046bf513b77c0c5639a0efc25f00e7f@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,avikivity/scylla,avikivity/scylla