west.yml: segger: RTT control block init mode Kconfigs

Kconfig options for RTT control block initialization and linker
section were added in #53569, however the Zephyr west.yml was not
updated to incorporate the Segger repository changes to make use
of the new Kconfig options.

This fixes that.

Signed-off-by: Bryce Wilkins <bryce.wilkins@gmail.com>