docs/arm64: elf_hwcaps: sort the HWCAP{, 2} documentation by ascending value

Part of the hardware capabilities documented in elf_hwcap.rst are
ordered following the definition in the header
arch/arm64/include/uapi/asm/hwcap.h but others seems to be documented
in random order.

To make easier to match against the definition in the header, they are
now sorted in the same order as they are defined in header. I.e.,
HWCAP first by ascending value, and then HWCAP2 in the similar fashion.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>