scsi: ufs: ufs-mediatek: Remove useless mediatek,ufs-boost-crypt property

There is no need to have a property that activates the inline crypto
boost feature, as this needs many things: a regulator, three clocks,
and the mediatek,boost-crypt-microvolt property to be set.

If any one of these is missing, the feature won't be activated,
hence, it is useless to have yet one more property to enable that.

While at it, also address another two issues:
1. Give back the return value to the caller and make sure to fail
   probing if we get an -EPROBE_DEFER or -ENOMEM; and
2. Free the ufs_mtk_crypt_cfg structure allocated in the crypto
   boost function if said functionality could not be enabled because
   it's not supported, as that'd be only wasted memory.

Last but not least, move the devm_kzalloc() call for ufs_mtk_crypt_cfg
to after getting the dvfsrc-vcore regulator and the boost microvolt
property, as if those fail there's no reason to even allocate that.

Fixes: ac8c2459 ("scsi: ufs-mediatek: Decouple features from platform bindings")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>