Remove tabs after spaces in C comments

This was not changed in HEAD, but will be done later as part of a
pgindent run.  Future pgindent runs will also do this.

Report by Tom Lane

Backpatch through all supported branches, but not HEAD

src/backend/lib/stringinfo.c

@@ -99,7 +99,7 @@ appendStringInfo(StringInfo str, const char *fmt,...)
  * appendStringInfoVA
  *
  * Attempt to format text data under the control of fmt (an sprintf-style
- * format string) and append it to whatever is already in str.	If successful
+ * format string) and append it to whatever is already in str.  If successful
  * return true; if not (because there's not enough space), return false
  * without modifying str.  Typically the caller would enlarge str and retry
  * on false return --- see appendStringInfo for standard usage pattern.
@@ -255,7 +255,7 @@ enlargeStringInfo(StringInfo str, int needed)
 	int			newlen;
 
 	/*
-	 * Guard against out-of-range "needed" values.	Without this, we can get
+	 * Guard against out-of-range "needed" values.  Without this, we can get
 	 * an overflow or infinite loop in the following.
 	 */
 	if (needed < 0)				/* should not happen */