fix typo in FPE_FLTUND definition, signal.h
diff --git a/include/signal.h b/include/signal.h
index 7f30be3..1a198e4 100644
--- a/include/signal.h
+++ b/include/signal.h
@@ -45,7 +45,7 @@
 #define FPE_INTOVF 2
 #define FPE_FLTDIV 3
 #define FPE_FLTOVF 4
-#define FPE_FLTUNT 5
+#define FPE_FLTUND 5
 #define FPE_FLTRES 6
 #define FPE_FLTINV 7
 #define FPE_FLTSUB 8