lvp: fixup multi draw memcpys
This doesn't fix the tests but it fixes a bunch of valgrind uninitialised value warnings
Fixes: f99f7c06 ("lavapipe: implement multidraw ext")
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This doesn't fix the tests but it fixes a bunch of valgrind uninitialised value warnings
Fixes: f99f7c06 ("lavapipe: implement multidraw ext")