It has been unused since 21732:eb34666befcc.
Removing the include of sys/ptrace.h and threaddb.h exposed a few
places which were using time(2) or gettimeofday(2) without including
time.h or sys/time.h respectively and were relying on an include.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>