mmc: core: Support zeroout using TRIM for eMMC

If an eMMC card supports TRIM and indicates that it erases to zeros, we can
use it to support hardware offloading of REQ_OP_WRITE_ZEROES, so let's add
support for this.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Reviewed-by: Avri Altman <Avri.Altman@wdc.com>
Link: https://lore.kernel.org/r/20220429152118.3617303-1-vincent.whitchurch@axis.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>