MINOR: samples: rename some struct member from "smp" to "data"

This members contains data and not sample.
diff --git a/include/proto/map.h b/include/proto/map.h
index 21ff57c..a63bc85 100644
--- a/include/proto/map.h
+++ b/include/proto/map.h
@@ -25,10 +25,10 @@
 #include <types/map.h>
 
 /* maps output sample parser */
-int map_parse_ip(const char *text, struct sample_data *smp);
-int map_parse_ip6(const char *text, struct sample_data *smp);
-int map_parse_str(const char *text, struct sample_data *smp);
-int map_parse_int(const char *text, struct sample_data *smp);
+int map_parse_ip(const char *text, struct sample_data *data);
+int map_parse_ip6(const char *text, struct sample_data *data);
+int map_parse_str(const char *text, struct sample_data *data);
+int map_parse_int(const char *text, struct sample_data *data);
 
 struct map_reference *map_get_reference(const char *reference);