add rpath for Solaris
diff --git a/auto/os/solaris b/auto/os/solaris
index 5a46ee6..f98c851 100644
--- a/auto/os/solaris
+++ b/auto/os/solaris
@@ -9,6 +9,8 @@
 CORE_SRCS="$UNIX_SRCS $SOLARIS_SRCS "
 CORE_LIBS="$CORE_LIBS -lsocket -lnsl -lrt"
 
+NGX_RPATH=YES
+
 # Solaris's make does not support a blank line between target and rules
 ngx_spacer=