CVE-2023-54157 binder: fix UAF of alloc->vma in race with munmap()

In the Linux kernel, the following vulnerability has been resolved: binder: fix UAF of alloc-vma in race with munmap cmllamas: clean forward port from commit 015ac18be7de "binder: fix UAF of alloc-vma in race with munmap" in 5.10 stable. It is needed in mainline after the revert of commit...