[ARM] Off-by-one in arch/arm/common/icst*

hi,

a quick find -iname \*.[ch] | xargs grep "> ARRAY_SIZE(", revealed
these in the icst drivers.
If i == ARRAY_SIZE, we get past the idx2s array.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>