frv: remove unused .altinstructions code

It appears that frv copied the .altinstructions definitions in its linker
script from x86. Since frv doesn't put anything in those sections, this
is just dead code.

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