rtsig uses own poll code

auto/os/linux

diff --git a/auto/os/linux b/auto/os/linux
index abf61f1..786b560 100644
--- a/auto/os/linux
+++ b/auto/os/linux
@@ -27,7 +27,6 @@
 if [ $version -ge 131609 -o $EVENT_RTSIG = YES ]; then
     echo " + rt signals found"
     have=NGX_HAVE_RTSIG . auto/have
-    have=NGX_HAVE_POLL . auto/have
     EVENT_MODULES="$EVENT_MODULES $RTSIG_MODULE"
     CORE_SRCS="$CORE_SRCS $RTSIG_SRCS"
     EVENT_FOUND=YES