FRV: Use __INIT macro instead of .text.init.

FRV is placing some code in the .text.init section but does not reference that
section in its linker scripts.

This change moves this code from the .text.init section to the .init.text
section, which is presumably where it belongs.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>