(werror): Removed incorrect noreturn attribute from declaration.

Rev: nettle/tools/misc.h:1.4

tools/misc.h

@@ -39,7 +39,6 @@ void
 werror(const char *format, ...)
 #if __GNUC___
      __attribute__((__format__ (__printf__,1, 2)))
-     __attribute__((__noreturn__))
 #endif
      ;