flash/nor/stellaris: fix: flash info RCC and RCC2 mixed up

flash/nor/stellaris: fix: flash info RCC and RCC2 mixed up

The flash info command on stellaris platformes
"TI/LMI Stellaris information ... rcc is ..., rcc2 is ..."
presented the actual RCC2 register as rcc and an uninitialized variable
as rcc2 due to a copy and paste error.
Found using the semantic pattern da/da.cocci, see coccinellery.org

Change-Id: I6f920fc3e07fdc085ea8e2248fbc9453eb8393dc
Signed-off-by: Alexander Kurz <akurz@blala.de>
Reviewed-on: http://openocd.zylin.com/3368
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>