util: add file exists check in virReadFCHost

File open errors are prevented by a file exists check before
virFileReadAll is called since all callers of the virReadFCHost
method handle errors themselves based on the NULL return anyway.
Also included is a minor spelling correction in a comment.
Signed-off-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>

src/util/virutil.c

@@ -2011,7 +2011,7 @@ virGetSCSIHostNameByParentaddr(unsigned int domain,
  *
  * Read the value of sysfs "fc_host" entry.
  *
- * Returns result as a stringon success, caller must free @result after
+ * Returns result as a string on success, caller must free @result after
  * Otherwise returns NULL.
  */
 char *
@@ -2029,6 +2029,9 @@ virReadFCHost(const char *sysfs_prefix,
                     host, entry) < 0)
         goto cleanup;
 
+    if (!virFileExists(sysfs_path))
+        goto cleanup;
+
     if (virFileReadAll(sysfs_path, 1024, &buf) < 0)
         goto cleanup;