For armv7 (cross build target): multimedia/libvpx depends on the GNU C library function getauxval and so fails to build; so, disable its <sys/auxv.h> expectation?

[Jan Beich]

Michal Meloun <melounmichal at gmail.com> writes:

> I don't think that full emulation of getauxval() is best -
> the port wants (from memory, incomplete) at least, additionally to
> AT_HWCAPS(2) :
>
> AT_PLATFORM
> AT_SECURE
> AT_RANDOM
> AT_CLKTCK
>
> I don't think that we want to implement linux compatible platform
> strings, nor generate random vector for each program.

elf_aux_info() is neither here nor there. I can't use it even for all
FreeBSD AT_* values unlike pass-through getauxval() e.g.,

    #if !defined(AT_EXECFN) && defined(AT_EXECPATH)
    #define AT_EXECFN AT_EXECPATH
    #endif
    
    printf("%s\n", (char *)getauxval(AT_EXECFN));