hidl_vec: mOwnsBuffer false by default

There was an extraneous set to make this true. I had left it alone while
making other changes just in case, but it should be safe to remove it
now.

Bug: N/A
Test: TH runs libhidl_test
Change-Id: I07122ac8202a69bd376c3b020735eddecaee8190
1 file changed