scsi-generic: Simplify error handling code

Coverity doesn't like the ignored return value introduced in
9d3b1551 (hw/block: Fix the return type), and other callers are
converted already in ceff3e1f.

This one was added lately in d9bcd6f7 and missed the train. Do it
now.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180118025245.13042-1-famz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

hw/scsi/scsi-generic.c

@@ -482,7 +482,6 @@ static void scsi_generic_realize(SCSIDevice *s, Error **errp)
     int rc;
     int sg_version;
     struct sg_scsi_id scsiid;
-    Error *local_err = NULL;
 
     if (!s->conf.blk) {
         error_setg(errp, "drive property not set");
@@ -516,11 +515,9 @@ static void scsi_generic_realize(SCSIDevice *s, Error **errp)
         error_setg(errp, "SG_GET_SCSI_ID ioctl failed");
         return;
     }
-    blkconf_apply_backend_options(&s->conf,
-                                  blk_is_read_only(s->conf.blk),
-                                  true, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
+    if (!blkconf_apply_backend_options(&s->conf,
+                                       blk_is_read_only(s->conf.blk),
+                                       true, errp)) {
         return;
     }