ARM: hwcaps: use shifts instead of hardcoded constants

The HWCAP numbers are defined as constants, each one being a power of 2.
This has become slightly unwieldy now that we have reached 32k.

This patch changes the HWCAP defines to use (1 << n) instead of coding
the constant directly. The values remain unchanged.

Signed-off-by: Will Deacon <will.deacon@arm.com>
ARM: hwcaps: add new HWCAP defines for ARMv7-A

Modern ARMv7-A cores can optionally implement these new hardware
features:

- VFPv4:
    The latest version of the ARMv7 vector floating-point extensions,
    including hardware support for fused multiple accumulate. D16 or D32
    variants may be implemented.

- Integer divide:
    The SDIV and UDIV instructions provide signed and unsigned integer
    division in hardware. When implemented, these instructions may be
    available in either both Thumb and ARM, or Thumb only.

This patch adds new HWCAP defines to describe these new features. The
integer divide capabilities are split into two bits for ARM and Thumb
respectively. Whilst HWCAP_IDIVA should never be set if HWCAP_IDIVT is
clear, separating the bits makes it easier to interpret from userspace.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Merge fail