ascli-actions-pkgmgr.c: "Fix" build on Windows

Like previous commits, avoid including unistd.h on Windows, and just bail out
trying to run package managers or flatpak as they are more or less concepts
that are foreign to Windows, at least for now.

tools/ascli-actions-pkgmgr.c

@@ -22,7 +22,11 @@
 
 #include <config.h>
 #include <glib/gi18n-lib.h>
+
+#ifndef G_OS_WIN32
 #include <unistd.h>
+#endif
+
 #include <errno.h>
 
 #include "ascli-utils.h"
@@ -41,6 +45,12 @@ exec_pm_action (const gchar *action, gchar **pkgnames)
 	const gchar *exe = NULL;
 	g_auto(GStrv) cmd = NULL;
 
+#ifdef G_OS_WIN32
+	g_printerr ("%s\n",
+				    _("No supported package managers are available on Windows."));
+			return ASCLI_EXIT_CODE_FAILED;
+#else
+
 #ifdef HAVE_APT_SUPPORT
 	if (g_file_test ("/usr/bin/apt", G_FILE_TEST_EXISTS))
 		exe = "/usr/bin/apt";
@@ -66,6 +76,7 @@ exec_pm_action (const gchar *action, gchar **pkgnames)
 	if (ret != 0)
 		ascli_print_stderr (_("Unable to spawn package manager: %s"), g_strerror (errno));
 	return ret;
+#endif
 }
 
 /**
@@ -80,6 +91,12 @@ exec_flatpak_action (const gchar *action, const gchar *bundle_id)
 	const gchar *exe = NULL;
 	g_auto(GStrv) cmd = NULL;
 
+#ifdef G_OS_WIN32
+	g_printerr ("%s\n",
+				    _("Flatpak is unavailable on Windows."));
+			return ASCLI_EXIT_CODE_FAILED;
+#else
+
 	exe = "/usr/bin/flatpak";
 	if (!g_file_test (exe, G_FILE_TEST_EXISTS)) {
 		g_printerr ("%s\n", _("Flatpak was not found! Please install it to continue."));
@@ -95,6 +112,7 @@ exec_flatpak_action (const gchar *action, const gchar *bundle_id)
 	if (ret != 0)
 		ascli_print_stderr (_("Unable to spawn Flatpak process: %s"), g_strerror (errno));
 	return ret;
+#endif
 }
 
 static int