manifest: update mcuboot to upmerged to upstream 1cb076c

MCUBoot was synchronized with upsteram
https://github.com/JuulLabs-OSS/mcuboot/commit/1cb076c

Signed-off-by: Andrzej Puzdrowski <andrzej.puzdrowski@nordicsemi.no>
diff --git a/west.yml b/west.yml
index f7bde1e..62dd718 100644
--- a/west.yml
+++ b/west.yml
@@ -89,7 +89,7 @@
       path: modules/crypto/mbedtls
       revision: 4bf099f1254332d16dcd931ccea0a88d24a7d3c7
     - name: mcuboot
-      revision: 9920005e1bedf20d0e2b24d39a44de193fc36691
+      revision: 813d29ca7ce2aeb388d945f7889e6711b97c33c7
       path: bootloader/mcuboot
     - name: mcumgr
       revision: cfe5eb98a9493017448846fd1a44a9340bd0a22f