strace: Change implementation to use ptrace()

Author: https://github.com/itamar8910
Commit: e5ebdb9bca
Pull-request: https://github.com/SerenityOS/serenity/pull/1517
Reviewed-by: https://github.com/awesomekling

Libraries/LibC/unistd.h

@@ -58,7 +58,6 @@ int get_process_name(char* buffer, int buffer_size);
 void dump_backtrace();
 int fsync(int fd);
 void sysbeep();
-int systrace(pid_t);
 int gettid();
 int donate(int tid);
 int set_process_icon(int icon_id);