Kinetis: FlexNVM handling

Kinetis: FlexNVM handling

FlexNVM (data flash) is memory mapped at 0x10000000.
Driver used to send the same address to FTFx controller for erase/write ops.
This was wrong as FTFx accepts only low 24 bits of address.
To fix addressing for flash controller kinfo->prog_base was introduced.

Added FlexNVM protection check, blank check and data flash size calculation.
Blank check cannot use block operation on FlexNVM when EEPROM backup is enabled.

Removed non functional reassign logic and bank_ordinal stuff.
Now one can re-probe FlexNVM banks after nvm_partition change.

Change-Id: Ia60b938266963e5d056701278cdf7bf2f62a429a
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/2987
Tested-by: jenkins