Fix incorrect comment in hba.h

A comment in hba.h mentioned that AuthTokens are used when building the
IdentLines from pg_ident.conf, but since 8fea868 that has added support
of regexps for databases and roles in pg_hba.conf, it is also the case
of HBA files.  This refreshes the comment to refer to both HBA and ident
files.

Issue spotted while going through a different patch.

src/include/libpq/hba.h

@@ -82,7 +82,7 @@ typedef enum ClientCertName
  * (pg_ident.conf or pg_hba.conf), together with whether the token has
  * been quoted.  If "string" begins with a slash, it may optionally
  * contain a regular expression (currently used for pg_ident.conf when
- * building IdentLines).
+ * building IdentLines and for pg_hba.conf when building HbaLines).
  */
 typedef struct AuthToken
 {