Add additional error handling to pcidev_readbar() callers

This is mostly a leftover of Niklas' "remove exit call from pcidev_init" patch.
While not explicitly necessary detecting errors early is usually a good idea.

Corresponding to flashrom svn r1718.

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/pcidev.c b/pcidev.c
index c7e9d78..3a3f77c 100644
--- a/pcidev.c
+++ b/pcidev.c
@@ -94,7 +94,7 @@
 
 	supported_cycles = pci_read_word(dev, PCI_COMMAND);
 
-	msg_pdbg("Requested BAR is ");
+	msg_pdbg("Requested BAR is of type ");
 	switch (bartype) {
 	case TYPE_MEMBAR:
 		msg_pdbg("MEM");