kArInfiniteTimeout warning

[flit]

(Issue reported by @diggit.)

There is one more warning:

./argon-rtos/include/argon/ar_kernel.h:54:26: warning: ISO C restricts enumerator values to range of 'int' [-Wpedantic]
     kArInfiniteTimeout = 0xffffffffUL   //!< Pass this value to wait forever to acquire a resource.

static const uint32_t kArInfiniteTimeout = 0xffffffffUL; would solve this warning, do/don't? (same would apply to kArNoTimeout for consistency

[flit]

The problem with using a static const for kArInfiniteTimeout and kArNoTimeout is that in C it would allocate storage (in .rodata) for these values. I'll look at this one and see if I can come up with something.

One option I've seen before is to cast the enum value to int, as in:

enum {
    kArInfiniteTimeout = (int)0xffffffffL,
};

But a quick test in Argon causes gcc 7.3.1 to report "comparison between signed and unsigned integer expressions" when comparing timeout parameters with this enum. So it needs more investigation.

Unfortunately, even moving to require C++11 or later wouldn't help here, since this is in the C API header ar_kernel.h.