[oe] invalid base-passwd_3.5.20.bb

[info]

Release 2011.3

At  ftp://ftp.debian.org/debian/pool/main/b/base-passwd/
these version is not available, so the building of all
images failes:
	base-passwd_3.5.20.tar.gz

verions 3.5.22 and 3.5.24 are available.

Please update the recipe.

Thank you, Roland