fix build of gperftools

Use siginfo_t instead of struct siginfo since the former is the POSIX standard and the latter breaks build on some Linux.

http://pubs.opengroup.org/onlinepubs/009695299/basedefs/signal.h.html

Change-Id: I52a8f0da93230f27f7e2ea41f754eb139c5eff3f
Signed-off-by: liuhuahang <liuhuahang@xiaomi.com>