Revert "pwm: atmel-tcb: Convert to platform remove callback returning void"

This reverts commit d4734ef7 which is
commit 9609284a upstream.

The remove_new platform callback is not in the Android tree, so revert
this commit which breaks the build (and is not really needed.)

Fixes: d4734ef7 ("pwm: atmel-tcb: Convert to platform remove callback returning void")
Change-Id: I6b255568ae27cd25b24c2d643656a43bf99fce4a
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>