Numerous opensolaris compilation fixes

For future note, opensolaris doesn't have sys/sysctl.h, doesn't like
comparing iov_buf to a chain_space_ptr without a cast, and is (predictably)
unforgiving of dumb syntax errors.

Also, we had accidentally broken the devpoll backend test in configure.in

arc4random.c

@@ -57,8 +57,10 @@
 #include <unistd.h>
 #include <sys/param.h>
 #include <sys/time.h>
+#ifdef _EVENT_HAVE_SYS_SYSCTL_H
 #include <sys/sysctl.h>
 #endif
+#endif
 #include <limits.h>
 #include <stdlib.h>
 #include <string.h>

buffer.c

@@ -615,7 +615,7 @@ evbuffer_commit_space(struct evbuffer *buf,
 		result = 0;
 		goto done;
 	} else if (n_vecs == 1 &&
-	    (buf->last && vec[0].iov_base == CHAIN_SPACE_PTR(buf->last))) {
+	    (buf->last && vec[0].iov_base == (void*)CHAIN_SPACE_PTR(buf->last))) {
 		/* The user only got or used one chain; it might not
 		 * be the first one with space in it. */
 		if (vec[0].iov_len > CHAIN_SPACE_LEN(buf->last))
@@ -641,7 +641,7 @@ evbuffer_commit_space(struct evbuffer *buf,
 	for (i=0; i<n_vecs; ++i) {
 		if (!chain)
 			goto done;
-		if (vec[i].iov_base != CHAIN_SPACE_PTR(chain) ||
+		if (vec[i].iov_base != (void*)CHAIN_SPACE_PTR(chain) ||
 		    vec[i].iov_len > CHAIN_SPACE_LEN(chain))
 			goto done;
 		chain = chain->next;

configure.in

@@ -287,7 +287,7 @@ if test "x$ac_cv_header_sys_devpoll_h" = "xyes"; then
 	AC_DEFINE(HAVE_DEVPOLL, 1,
 		    [Define if /dev/poll is available])
 fi
-AM_CONDITIONAL(DEVPOLL_BACKEND, [test "ac_cv_header_sys_devpoll_h" = "xyes"])
+AM_CONDITIONAL(DEVPOLL_BACKEND, [test "x$ac_cv_header_sys_devpoll_h" = "xyes"])
 
 havekqueue=no
 if test "x$ac_cv_header_sys_event_h" = "xyes"; then

evport.c

@@ -124,7 +124,8 @@ const struct eventop evportops = {
 	evport_dispatch,
 	evport_dealloc,
 	1, /* need reinit */
-	0
+	0, /* features */
+	0, /* fdinfo length */
 };
 
 /*