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>

west.yml

@@ -317,7 +317,7 @@ manifest:
       path: modules/lib/picolibc
       revision: d492d5fa7c96918e37653f303028346bb0dd51a2
     - name: segger
-      revision: 798f95ea9304e5ed8165a661081443051f210733
+      revision: pull/17/head
       path: modules/debug/segger
       groups:
         - debug