ANDROID: trusty: Get rid of 'remove_new' relic from platform driver struct

Following on from Linus's change in Mainline, we have to convert all
.remove_new operation back to .remove. To support back to 5.10, we need
to handle the int return value for kernels less than v6.12.

Fixes: e70140ba0d2b ("Get rid of 'remove_new' relic from platform driver struct")
Change-Id: I130fb574b11207a4518f0dfdc5fe6cd3c12ae6ce
Signed-off-by: Lee Jones <joneslee@google.com>
Signed-off-by: Will McVicker <willmcvicker@google.com>