mm/codetag: fix arg in pgalloc_tag_copy alloc_tag_sub

alloc_tag_sub() takes bytes as opposed to number of pages as argument.

Currently pgalloc_tag_copy() passes the number of pages.  This fix passes
the correct unit, which is the number of bytes allocated.

Link: https://lkml.kernel.org/r/20241022232440.334820-1-souravpanda@google.com


Fixes: e0a955bf ("mm/codetag: add pgalloc_tag_copy()")
Signed-off-by: Sourav Panda <souravpanda@google.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>