ANDROID: mm/slub: Fix Kasan issue with get_each_kmemcache_object

In get_each_kmemcache_object  we go through meta data of the slab
object in function(fn), and as a result false postive out-of-bound
access is reported by kasan. Fix this by wrapping that function call
with metadata_access_enable/disable.

Bug: 222651868
Fixes: I8b920f6bd770 ("ANDROID: mm: Add helper function to iterate over slab objects")
Change-Id: Ifb4241a9c3e397a52759d467aa267d1297e297dd
Signed-off-by: Vijayanand Jitta <quic_vjitta@quicinc.com>
Signed-off-by: Oreoluwa Babatunde <quic_obabatun@quicinc.com>