west.yml: MCUboot synchronization from v3.7-branch

Update Zephyr fork of MCUboot to revision:
  6127fc06a54d7a364626a96a33ae652703b505e4

Brings following Zephyr relevant fixes:

  - 6127fc06 bootutil: Fixed security counter overflow detected to
    late
  - 45f96eb7 boot/boot_serial: build-time skip of the erasing of
    img status page
  - a3166c52 boot: zephyr: boards: nrf52: Fix minimal config
  - 29ea8ef4 boot: zephyr: Remove reference to old Kconfigs
  - 0c1950df boot: bootutil: image_validate: Add error on security
    counter fail
  - 4d2f3b7f bootutil: Remove pointless includes of asn1 headers
  - 9d7d58d9 boot: bootutil: declare fih_panic_loop() as noreturn
  - 11c0611a bootutil: Unify app_max_size() implementations

Signed-off-by: Jamie McCrae <jamie.mccrae@nordicsemi.no>