sparc: support the ADP hw capability

This patch adds support for the ADP (also known as adi) hardware
capability, as reported by the kernel sparc port when running on M7
machines.

Tested in both sparcv9-*-* and sparc64-*-* targets.

	* sysdeps/sparc/bits/hwcap.h (HWCAP_SPARC_ADP): Defined.
	* sysdeps/sparc/dl-procinfo.c: Added "adp" to the
	_dl_sparc_cap_flags array.
	* sysdeps/sparc/dl-procinfo.h (_DL_HWCAP_COUNT): Increment.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>