manifest: mcuboot update

MCUboot fork was updated in order to bring bugfixes from its
upstream:
- introduce MCUBOOT_CPU_IDLE() for support low power single thread
(fixes single thread power consumption)
- Allow not working secondary image device and boot form primary
device if image available
- fixes memory alignment of the RAM buffer that is used to temporarily
store data during swap.
- update devicetree py package lib files include path in assembly
- serial recovery: cbor_encoder: fix str encoding macros
- zephyr: Kconfig: fix board references
- do not set defaults for LOG_IMMEDIATE Kconfig
- boot: Do not use `irq_lock()` if using arm cleanup
- Kconfig: fix deadlock on cryptolib selectors

Signed-off-by: Andrzej Puzdrowski <andrzej.puzdrowski@nordicsemi.no>