sr: Consistently use 512kB as default chunk size.

input/binary.c

@@ -25,7 +25,7 @@
 #include <sys/time.h>
 #include "sigrok.h"
 
-#define CHUNKSIZE          4096
+#define CHUNKSIZE             (512 * 1024)
 #define DEFAULT_NUM_PROBES    8
 
 static int format_match(const char *filename)

session_driver.c

@@ -27,7 +27,7 @@
 #include "sigrok-internal.h"
 
 /* size of payloads sent across the session bus */
-#define CHUNKSIZE 4096
+#define CHUNKSIZE (512 * 1024)
 
 struct session_vdevice {
 	char *capturefile;

sigrok-internal.h

@@ -34,7 +34,7 @@
 #endif
 
 /* Size of a datastore chunk in units */
-#define DATASTORE_CHUNKSIZE 512000
+#define DATASTORE_CHUNKSIZE (512 * 1024)
 
 /*--- hwplugin.c ------------------------------------------------------------*/