security/krb5*: Disable NLS when option is deselected

When the NLS option is deselected, ./configure reverts to
enable_nls=check. As some prerequisites do require NLS, NLS is
always enabled even when deslected. This ensures that when NLS
is not wanted, that it is not used, regardless of its install status.

(cherry picked from commit 0b58b7b475e3100adfb3b532f2dfb9505e79bf83)