ARM: 8349/1: arch/arm/mm/proc-arm925.S: remove dead #ifdef block

The block could never be compiled;  CPU_ICACHE_STREAMING_DISABLE has not
been defined in Kconfig since the very first Git commit.  Hence, we can
safely remove the entire block.

Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>