posix-timers: Plug potential memory leak in do_timer_create()

In the Linux kernel, the following vulnerability has been resolved: posix-timers: Plug potential memory leak in do_timer_create() When posix timer creation is set to allocate a given timer ID and the access to the user space value faults, the function terminates without freeing the already allocated posix timer structure. Move the allocation after the user space access to cure that. [ tglx: Massaged change log ]