riscv: dts: starfive: jh7110-common: drop mmc post-power-on-delay-ms

riscv: dts: starfive: jh7110-common: drop mmc post-power-on-delay-ms

Drop post-power-on-delay-ms from mmc0 mmc1 interfaces. There is no
known reason for these properties to continue, testing appears to be fine
without them [1].

1: https://lore.kernel.org/lkml/NT0PR01MB1312E0D9EE9F158A57B77700E63D2@NT0PR01MB1312.CHNPR01.prod.partner.outlook.cn/

Signed-off-by: E Shattow <e@freeshell.de>
Tested-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
[ upstream commit: b5a861a438d1a456952665cf6167969f01209479 ]

(cherry picked from commit 9c18e97b9be437c97789c9687148f3dd3f25b809)