sunrpc: fix uninitialized xprt_create_args structure

In the Linux kernel, the following vulnerability has been resolved: sunrpc: fix uninitialized xprt_create_args structure The xprt_create_args structure is allocated on the stack without initialization in rpc_sysfs_xprt_switch_add_xprt_store(). While some fields are manually populated, critical fields like srcaddr, bc_xps, and flags contain uninitialized stack garbage. This can lead to: 1. Kernel panic when xs_setup_xprt() dereferences garbage srcaddr 2. Information leak if srcaddr points to sensitive stack data 3. Unpredictable behavior if flags has random bits set The fix is to zero-initialize the structure to ensure all unused fields are NULL/0, preventing the transport setup code from acting on garbage data.