[PATCH] cfi_cmdset_0001: fix range for cache invalidation

I found an issue in cfi_cmdset0001.c.  It is related to cache region
invalidation in the buffered write procedure.

The code performs cache invalidation from "cmd_addr" to "cmd_adr + len" in
do_write_buffer() while we modify region from "adr" to "adr+len".

This issue affects writes + reads of data by small chunks.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>