nfs-utils: exports man page: no_acl is not supported

nfs-utils: exports man page: no_acl is not supported

The inclusion of no_acl in the exports man page is confusing since it is
not actually supported (v3.3-rc3):

1090 static struct flags {
1091         int flag;
1092         char *name[2];
1093 } expflags[] = {
1094         { NFSEXP_READONLY, {"ro", "rw"}},
1095         { NFSEXP_INSECURE_PORT, {"insecure", ""}},
1096         { NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
1097         { NFSEXP_ALLSQUASH, {"all_squash", ""}},
1098         { NFSEXP_ASYNC, {"async", "sync"}},
1099         { NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
1100         { NFSEXP_NOHIDE, {"nohide", ""}},
1101         { NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
1102         { NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
1103         { NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
1104         { NFSEXP_V4ROOT, {"v4root", ""}},
1105         { 0, {"", ""}}
1106 };

Signed-off-by: Harshula Jayasuriya <harshula@redhat.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Steve Dickson <steved@redhat.com>