firmware-utils: fix various compiler warnings

mostly implicit defines due to missing includes plus one const that
shouldn't be one.

Signed-off-by: Felix Kaechele <felix@kaechele.ca>

SVN-Revision: 47865

tools/firmware-utils/src/srec2bin.c

@@ -513,7 +513,7 @@ int srec2bin(int argc,char *argv[],int verbose)
     return(1);
 }
 
-main(int argc, char *argv[])
+int main(int argc, char *argv[])
 {
     debug = TRUE;
     debug = FALSE;