added print hook for certinfo_t printing

src/libstrongswan/printf_hook.h

@@ -60,6 +60,8 @@
 #define PRINTF_TIME_DELTA		'V'
 /** 1 argument: ca_info_t *ca_info; with #-modifier 2 arguments: ca_info_t *ca_info, bool utc */
 #define PRINTF_CAINFO			'W'
+/** 1 argument: certinfo_t *certinfo; with #-modifier 2 arguments: certinfo_t *certinfo, bool utc */
+#define PRINTF_CERTINFO			'X'
 
 /**
  * Generic arginfo handlers for printf() hooks