Remove more exit calls

This patch removes the remaining exit calls from
 - sp_openserport
 - sp_opensocket
 - sp_docommand
 - internal_init

Almost all of this was done by Niklas.

Corresponding to flashrom svn r1557.

Signed-off-by: Niklas Söderlund <niso@kth.se>
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
diff --git a/pony_spi.c b/pony_spi.c
index b5dfc2f..6ce467e 100644
--- a/pony_spi.c
+++ b/pony_spi.c
@@ -99,6 +99,10 @@
 
 	if (arg && strlen(arg)) {
 		sp_fd = sp_openserport( arg, 9600 );
+		if (sp_fd < 0) {
+			free(arg);
+			return 1;
+		}
 		have_device++;
 	}
 	free(arg);