Module build is broken since commit c261d774 ( rules.mak: Fix DSO
build by pulling in archive symbols). That commit added .mo placeholders
of DSO to -y variables, in order to pull stub symbols to executable. But
the placeholders are unintentionally expanded in -y, rather than
filtered out while linking.

Fix it by moving the -objs expanding to before inserting .mo
placeholders.  Note that passing -cflags and -libs to member objects are
also moved to keep it happening before object expanding.

Reported-by: Bharata B Rao <bharata.rao@gmail.com>
Tested-by: Bharata B Rao <bharata.rao@gmail.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>