fs/ntfs3: Initialize allocated memory before use

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: Initialize allocated memory before use

KMSAN reports: Multiple uninitialized values detected:

• KMSAN: uninit-value in ntfs_read_hdr (3)
• KMSAN: uninit-value in bcmp (3)

Memory is allocated by __getname(), which is a wrapper for kmem_cache_alloc(). This memory is used before being properly cleared. Change kmem_cache_alloc() to kmem_cache_zalloc() to properly allocate and clear memory before use.