module: wrapper for symbol name.

[ Upstream commit 2e7bac536106236104e9e339531ff0fcdb7b8147 ]

This trivial wrapper adds clarity and makes the following patch
smaller.

Cc: stable@kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>