tune-cortexa72: remove crypto for the default cortex-a72

The cryptographic unit is optional for the Cortex-A72, but it was
included by default previously.  This breaks building systems that
lack this functionality when using tune-cortexa72.inc.

To correct this, add a crypto entry in the tune file.  Since CRC is
optional for ARMv8.0, do the same thing while we're at it.

For platforms that had been happily using tune-cortexa72.inc, a slight
degradation of performance will occur using the default.  To correct
this, simply add:
DEFAULTTUNE = "cortexa72-crc-crypto"

Signed-off-by: Jagadeesh Krishnanjanappa <workjagadeesh@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us> (rewording commit message)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>