do not use `a' quoting style in comments

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/util-linux/fdisk_osf.c b/util-linux/fdisk_osf.c
index 89f1f32..1141b78 100644
--- a/util-linux/fdisk_osf.c
+++ b/util-linux/fdisk_osf.c
@@ -18,7 +18,7 @@
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE