CVE-2024-57878 arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR

In the Linux kernel, the following vulnerability has been resolved: arm64: ptrace: fix partial SETREGSET for NTARMFPMR Currently fpmrset doesn't initialize the temporary 'fpmr' variable, and a SETREGSET call with a length of zero will leave this uninitialized. Consequently an arbitrary value will...