package.bbclass: Fix shlibs cross package-arch contamination

package.bbclass: Fix shlibs cross package-arch contamination

I found that if I had two packages architectures built (say core2 and i586),
that the shlibs data from i586 was being used in the core2 build. This
lead to odd dependency issues if the i586 build was out of date and core2
was being targetted.

When loading shlibs files, the last loaded wins so we need to iterate the
lists from least to strongest weighting, not the other way around. With this
patch applied, the contamination issue is resolved.

(From OE-Core rev: acd7b1c2ee9f3ff84c45a723dba5e0bc5f6a100c)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>