libeventlog: use common header for ANSI colors

Problem: libeventlog/formatter.c defines ANSI color terminal escapes
but they are now defined in a common header.

Use ansi_color.h.

Author: garlick

src/common/libeventlog/formatter.c

@@ -23,25 +23,11 @@
 #include "ccan/str/str.h"
 #include "src/common/libutil/errprintf.h"
 #include "src/common/libutil/timestamp.h"
+#include "src/common/libutil/ansi_color.h"
 
 #include "eventlog.h"
 #include "formatter.h"
 
-#define ANSI_COLOR_RED        "\x1b[31m"
-#define ANSI_COLOR_GREEN      "\x1b[32m"
-#define ANSI_COLOR_YELLOW     "\x1b[33m"
-#define ANSI_COLOR_BLUE       "\x1b[34m"
-#define ANSI_COLOR_MAGENTA    "\x1b[35m"
-#define ANSI_COLOR_CYAN       "\x1b[36m"
-#define ANSI_COLOR_GRAY       "\x1b[37m"
-
-#define ANSI_COLOR_RESET      "\x1b[0m"
-#define ANSI_COLOR_BOLD       "\x1b[1m"
-#define ANSI_COLOR_HALFBRIGHT "\x1b[2m"
-#define ANSI_COLOR_REVERSE    "\x1b[7m"
-
-#define ANSI_COLOR_RESET      "\x1b[0m"
-
 enum {
     EVENTLOG_COLOR_NAME,
     EVENTLOG_COLOR_TIME,