daemon: augeas: Don't test if AUG_NO_ERR_CLOSE is defined.

It's an enum, not a macro, and in any case it has been present in
augeas.h since 0.10.0, and the minimum version that libguestfs
requires is 1.0.0.

This fixes commit 3d132f29204e8c5c77f08841b5288dfe3013f4f0.