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

Update Zephyr fork of MCUboot to revision:
  7a29b5a6a10f9179cac3935645c2a1356dafb2b6

Brings following Zephyr relevant fixes:

  - 70ad2d44 boot: bootutil: Fix serial recovery issues
  - 4e659a94 boot: bootutil: Fix wrong define for single loader
    mode
  - 8f6f4b4b boot: bootutil: Fix single loader trailer size
  - 99cecb5a boot: boot_serial: Fix wrong slot ID for hook calls
  - 3519605c zephyr: cleanup removed
    CONFIG_BOOT_MGMT_CUSTOM_IMG_LIST
  - 86dc36ed boot_serial: Avoid re-initializing state in
    boot_image_validate_encrypted
  - 16472e08 boot_serial: Initialize a bootloader state for bs_list
    and bs_set
  - 5ee8ede0 zephyr: Fix pinreset trigger
  - f448629c bootutil: boot_decrypt_key: Only one
    bootutil_hmac_sha256_drop needed
  - 2f5d6bf9 imgtool: fix dependency on click version
  - 50c14ceb boot: bootutil: bootutil_misc: Fix max image size for
    single images
  - 18d9df1f bootutil: Fix crash when bootutil_sha_init() is called
    in loop
  - c2f2f90d boot: bootutil: Only update the security counter for
    confirmed images
  - 5a7ee345 boot: bootutil: Fix max image size computation for
    swap-move/swap-offset
  - 116925f7 boot/zephyr/main: fix placement of pointer to arm
    vector
  - b4cff578 boot: bootutil: swap_scratch: Fix issue with bricking
    device
  - 480464d2 boot: bootutil: Refactor erase functionality to fix
    watchdog feeding
  - cc38cc27 boot: Use boot erase function instead of flash erase
    function
  - bb148939 boot: zephyr: flash_map: Fix missing include
  - 51620768 boot: boot_serial: Fix issue with CBOR and setting
    image state
  - a277cf03 zephyr: Fix trailer size computation for swap-scratch
  - ac0ac75e zephyr: Fix TLV area was included in trailer size when
    rounding up
  - 25922090 boot: bootutil: swap_move: Fix maximum application
    size

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