copy SIGPOLL test from fptools/configure.ac for System.Posix.Signals (dunno why they can't just #ifdef SIGPOLL instead of #if HAVE_SIGPOLL)
copy SIGPOLL test from fptools/configure.ac for System.Posix.Signals
(dunno why they can't just #ifdef SIGPOLL instead of #if HAVE_SIGPOLL)

FranklinChen/Hugs,FranklinChen/Hugs,FranklinChen/Hugs,FranklinChen/Hugs,FranklinChen/Hugs,FranklinChen/Hugs,FranklinChen/Hugs