Avoid overexposure of an internal mask. EOF_SET -> EOF_IS

Also, use PPSDRIFT_SET as a client-side status flag for JSON PPS rather
than the (not yet shipped) TIMEDRIFT_SET.  Next release we're probably
going to add a drift object for in-line time.

No logic changes.  All regression tests pass.

1 files changed, 1 insertions, 1 deletions

diff --git a/gps.h b/gps.h
index c7515510..15467f25 100644
--- a/gps.h
+++ b/gps.h
@@ -1957,7 +1957,7 @@ struct gps_data_t {
 #define LOGMESSAGE_SET	(1llu<<30)
 #define ERROR_SET	(1llu<<31)
 #define TIMEDRIFT_SET	(1llu<<32)
-#define EOF_SET		(1llu<<33)
+#define PPSDRIFT_SET	(1llu<<33)
 #define SET_HIGH_BIT	34
     timestamp_t online;		/* NZ if GPS is on line, 0 if not.
 				 *