fix sparc32 breakage (result of vmlinux.lds.S bug)

In commit 4665079c ("[NETNS]: Move some
code into __init section when CONFIG_NET_NS=n") we got a new section -
.exit.text.refok (more of 'let's tell modpost that some bogus calls are
not bogus', a-la text.init.refok).

Unfortunately, the commit in question forgot to add it to TEXT_TEXT,
with rather amusing results.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>