ARM: Add support for AT_HWCAP2 in _dl_procinfo

ARM: Add support for AT_HWCAP2 in _dl_procinfo

Add support for the new HWCAP2 values for ARMv8 added in the
3.15 kernel. Tested using QEMU which supports these extensions.

ChangeLog:

2014-06-25  Will Newton  <will.newton@linaro.org>

	* sysdeps/unix/sysv/linux/arm/dl-procinfo.c
	(_dl_arm_cap_flags): Add HWCAP2 values.
	* sysdeps/unix/sysv/linux/arm/dl-procinfo.h
	(_DL_HWCAP_COUNT): Increase to 37.
	(_DL_HWCAP_LAST): New define.
	(_DL_HWCAP2_LAST): New define.
	(_dl_procinfo): Add support for printing
	AT_HWCAP2 entries.
	(_dl_string_hwcap): Use _dl_hwcap_string.