Revert "Revert "emulator: create qemu images for system,vendor""

This reverts commit 9b99ddc8.
and add syste-qemu.img to the dependency list of sdk target

BUG: 64235252

Test: build sdk target successfully

(cherry picked from commit f0d50bbe)

Change-Id: I813233c7c3f06eb1eca18aad5ea890a55814eb1b