binfmt_elf: elf_bss no longer used by load_elf_binary()

binfmt_elf: elf_bss no longer used by load_elf_binary()

With the BSS handled generically via the new filesz/memsz mismatch
handling logic in elf_load(), elf_bss no longer needs to be tracked.
Drop the variable.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-mm@kvack.org
Suggested-by: Eric Biederman <ebiederm@xmission.com>
Tested-by: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Sebastian Ott <sebott@redhat.com>
Link: https://lore.kernel.org/r/20230929032435.2391507-2-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>