yet more mingw w64 build

Fix:
../sys/winnt/nhraykey.c: In function 'CheckInput':
../sys/winnt/nhraykey.c:459:37: warning: type of 'mode' defaults to 'int' [-Wimplicit-int]
 int __declspec(dllexport) __stdcall CheckInput(hConIn, ir, count, numpad,
                                     ^~~~~~~~~~

win/curses/cursdial.c

@@ -10,10 +10,10 @@
 #include "func_tab.h"
 #include <ctype.h>
 
-#if defined(FILENAME_CMP)
+#if defined(FILENAME_CMP) && !defined(strcasecmp)
 #define strcasecmp FILENAME_CMP
 #endif
-#if defined(STRNCMPI)
+#if defined(STRNCMPI) && !defined(strncasecmp)
 #define strncasecmp strncmpi
 #endif