Adding stub function to get clean builds on Solaris 
contributed upstream for review - https://gitlab.gnome.org/GNOME/libgtop/issues/47

Taken from the darwin changes, so leaving their Copyright in

--- a/sysdeps/solaris/glibtop_server.h	2019-09-25 12:45:36.788121763 -0700
+++ b/sysdeps/solaris/glibtop_server.h	2019-09-25 12:46:01.849408898 -0700
@@ -53,8 +53,9 @@
 #define GLIBTOP_SUID_PROC_WD		0
 #define GLIBTOP_SUID_PPP		0
 #define GLIBTOP_SUID_PROC_AFFINITY	0
+#define GLIBTOP_SUID_PROC_OPEN_FILES   0
+#define GLIBTOP_SUID_PROC_IO    	0
 
-
 G_END_DECLS
 
 #endif
--- /dev/null	2019-09-25 18:40:51.520550102 -0700
+++ b/sysdeps/solaris/procio.c	2019-09-25 18:40:39.213705245 -0700
@@ -0,0 +1,45 @@
+/* Copyright (C) 2018 Benoît Dejean
+   This file is part of LibGTop.
+
+   Contributed by Benoît Dejean <bdejean@gmail.com>, February 2018.
+
+   LibGTop is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License,
+   or (at your option) any later version.
+
+   LibGTop is distributed in the hope that it will be useful, but WITHOUT
+   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+   for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with LibGTop; see the file COPYING. If not, write to the
+   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+
+#include <config.h>
+#include <glibtop.h>
+#include <glibtop/error.h>
+#include <glibtop/procio.h>
+
+static const unsigned long _glibtop_sysdeps_proc_io;
+
+/* Init function. */
+
+void
+_glibtop_init_proc_io_s (glibtop *server)
+{
+	server->sysdeps.proc_io = _glibtop_sysdeps_proc_io;
+}
+
+/* Provides detailed information about a process. */
+
+void
+glibtop_get_proc_io_s (glibtop *server, glibtop_proc_io *buf, pid_t pid)
+{
+    memset (buf, 0, sizeof (glibtop_proc_io));
+    buf->flags = _glibtop_sysdeps_proc_io;
+}
+
--- a/sysdeps/solaris/Makefile.am	2019-09-25 13:11:15.502663428 -0700
+++ b/sysdeps/solaris/Makefile.am	2019-09-25 13:15:01.986761006 -0700
@@ -17,7 +17,8 @@
 libgtop_sysdeps_2_0_la_LIBADD	= @DL_LIB@
 
 libgtop_sysdeps_suid_2_0_la_SOURCES	= open_suid.c close_suid.c \
-				  shm_limits.c msg_limits.c sem_limits.c
+				  shm_limits.c msg_limits.c sem_limits.c \
+			          procio.c
 
 libgtop_sysdeps_suid_2_0_la_LDFLAGS	= $(LT_VERSION_INFO)