mm, slab: don't wrap internal functions with alloc_hooks()

The functions __kmalloc_noprof(), kmalloc_large_noprof(),
kmalloc_trace_noprof() and their _node variants are all internal to the
implementations of kmalloc_noprof() and kmalloc_node_noprof() and are
only declared in the "public" slab.h and exported so that those
implementations can be static inline and distinguish the build-time
constant size variants. The only other users for some of the internal
functions are slub_kunit and fortify_kunit tests which make very
short-lived allocations.

Therefore we can stop wrapping them with the alloc_hooks() macro and
drop the _noprof suffix. Instead add a __prefix where missing and a
comment documenting these are internal. Also rename __kmalloc_trace() to
__kmalloc_cache() which is more descriptive - it is a variant of
__kmalloc() where the exact kmalloc cache has been already determined.

Reported-by: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>