alloc_tag: check mem_profiling_support in alloc_tag_init

alloc_tag: check mem_profiling_support in alloc_tag_init

If mem_profiling_support is false, for example by
sysctl.vm.mem_profiling=never, alloc_tag_init should skip module tags
allocation, codetag type registration and procfs init.

Link: https://lkml.kernel.org/r/20250513182602.121843-1-cachen@purestorage.com
Signed-off-by: Casey Chen <cachen@purestorage.com>
Reviewed-by: Yuanyuan Zhong <yzhong@purestorage.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>