[roll] Roll fuchsia [wlan][policy] Use new signal related structs

Change numerical usages of emwa to use the EwmaSignalStrength struct. Change
numerical uses of dBm to use the DecibelMilliWatt struct. Fix the velocity
function to specify it is linear, and add overflow checking. Move it to a
separate wlan-common library. Also, broaden the language, since these
functions can apply to any dBm measurement, not just RSSI.

Original-Bug: 91873
Test: fx test wlancfg-tests
Test: fx test wlan-common-tests
Multiply: wlancfg-tests
Multiply: wlan-common-tests
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/617668
Original-Revision: 1d82a24d7fbe5bb3d53bdd9b368bafb6a3b58760
GitOrigin-RevId: a412d668c7f5fd808da157f4ea83f0ad47dc54f3
Change-Id: Ie3bb061023c093780a07caca702e3eba9107b1e9
diff --git a/stem b/stem
index 219b89f..6c046de 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="6ed375cfba368ddb4e0c3a0f8fbe1ab5dfce004e"/>
+             revision="1d82a24d7fbe5bb3d53bdd9b368bafb6a3b58760"/>
   </projects>
   <hooks>
     <hook name="install-environment"