Now that LD_HWCAP_MASK (or glibc.tune.hwcap_mask) is read early enough
to influence cpu feature check in aarch64, use it to influence
multiarch selection. Setting LD_HWCAP_MASK such that it clears
HWCAP_CPUID will now disable multiarch for the binary.
HWCAP_CPUID is also now set in HWCAP_IMPORTANT so that it is set by
default. With this patch, this feature is only usable with
dyanmically linked binaries because LD_HWCAP_MASK is not read for
static binaries. A future patch fixes that.
* sysdeps/unix/sysv/linux/aarch64/cpu-features.c
(init_cpu_features): Use glibc.tune.hwcap_mask.
* sysdeps/unix/sysv/linux/aarch64/dl-procinfo.h: New file.