Fix -fno-common build failure.

Index: src/typespeed.h
--- src/typespeed.h.orig
+++ src/typespeed.h
@@ -56,7 +56,7 @@ struct stats {
 	clock_t duration;
 	unsigned int sinit;
 	char name[21];
-} now;
+};
 
 struct opt {
 	int cheat;
@@ -66,7 +66,7 @@ struct opt {
 	int usecolors;
 	char name[21];
 	char order[3];
-} opt;
+};
 
 struct rules {
 	int misses;
@@ -85,12 +85,12 @@ struct rules {
 	int maxtime;
 	char name[31];
 	char fname[FILENAME_MAX + 1];
-} rules;
+};
 
 struct rawdata {
 	char *bulk;
 	char **word;
 	size_t n;
 	size_t max;
-} words;
+};
 
