Add code related to sw64 in file configure configure.ac aclocal.m4 lib/blkid/llseek.c lib/ext2fs/unix_io.c to support sw64 architecture. Signed-off-by: wzx <wuzx1226@qq.com> (cherry picked from commit a30236cefb9a0e9c119a1a18c1a95ed8bf3e736b)
