docs: release-notes: Add note on zephyr boot banner fix

Adds a note that this issue has been fixed

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

Author: nordicjm

docs/release-notes.d/zephyr-banner.md

@@ -0,0 +1,5 @@
+- Zephyr MCUboot boot banner has been fixed after changes
+  made to the boot banner after Zephyr 4.4. Note that the order
+  has changed, previously the MCUboot version would be output
+  first, now the Zephyr version (if `CONFIG_BOOT_BANNER` if
+  enabled) will be output first.