mips/c-r4k: remove legacy __cpuinit section that crept in

We removed __cpuinit support (leaving no-op stubs) quite some time ago.
However a new instance was added in commit 4caa906e
("MIPS: mm: c-r4k: Build EVA {d,i}cache flushing functions")

Since we want to clobber the stubs soon, get this removed now.

Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>