Keep vbutil_ec from dying if EC firmware B isn't present

BUG=chrome-os-partner:11451
TEST=build bds firmware with ifdef CONFIG_FW_B removed from config.h

Change-Id: I74ef0258988e065f602e4564e3b49903b34013c5
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/27655
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
diff --git a/utility/vbutil_ec.c b/utility/vbutil_ec.c
index c1b280f..4aa0d3f 100644
--- a/utility/vbutil_ec.c
+++ b/utility/vbutil_ec.c
@@ -330,7 +330,9 @@
     sprintf(buf, "FW_MAIN_%c", i);
     if (!FindInFmap(fmap, buf, image, image_size, &fv_data, &fv_size)) {
       printf("Can't find %s in %s\n", buf, filename);
-      errorcnt++;
+      /* Not an error for firmware B */
+      if (i != 'B')
+        errorcnt++;
       continue;
     }
 
@@ -338,7 +340,9 @@
     if (!FindInFmap(fmap, buf, image, image_size,
                     (uint8_t **)&key_block, &key_block_size)) {
       printf("Can't find %s in %s\n", buf, filename);
-      errorcnt++;
+      /* Not an error for firmware B */
+      if (i != 'B')
+        errorcnt++;
       continue;
     }