cryptodev: update GMAC API comments
cryptodev: update GMAC API comments

In file rte_crypto_sym.h, GMAC API comments need to be changed
to comply with the GMAC specification. Main areas of change are
aad pointer and aad len, which now will be used to
provide plaintext.

Signed-off-by: Arek Kusztal <4bf5ef838d7576d5719b17cd64a25f70d57e7e5b@intel.com>
Acked-by: Deepak Kumar Jain <9bf453c83e22b0c9e2b3754d419540ea41e2427f@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk