xtensa: mm/cache: add missing EXPORT_SYMBOLs

commit bc652eb6a0d5cffaea7dc8e8ad488aab2a1bf1ed upstream.

Functions clear_user_highpage, copy_user_highpage, flush_dcache_page,
local_flush_cache_range and local_flush_cache_page may be used from
modules. Export them.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
[bwh: Backported to 3.2: drop exports of {clear,copy}_user_highpage()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --cc arch/xtensa/mm/cache.c
Simple merge