[NET, HAL] K64F - enet edit for new header files (address used instead of instance)

	- hal enet - asserts commented out as they are not valid for new MCU headers (address, no instance)
	- net - corrections for new ksdk API
Merge pull request #504 from 0xc0170/fix_enet_k64f_ksdk

[NET, HAL] K64F - update files to use address of enet peripheral (not instance as required by KSDK v1.0)