trace-cmd: Replace bufcpy() with msgcpy() and optcpy() The bufcpy() wrapper to memcpy() is not very useful except that it may save on a typecast. Create a msgcpy() and optcpy() to use instead that is type safe and also allows for checking of memory size overflows in the future. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>