Remove external/messageformat

external/messageformat is unused in the platform
Bug: 63809499
Test: build
Merged-In: If26b67f868ae1377efccf49c1b6bf086d4b43415
Merged-In: I478fa7791328539bdd8826cdec1dc9f36f8cbfdc
Change-Id: I478fa7791328539bdd8826cdec1dc9f36f8cbfdc

default.xml

@@ -254,7 +254,6 @@
   <project path="external/markdown" name="platform/external/markdown" groups="pdk" />
   <project path="external/mdnsresponder" name="platform/external/mdnsresponder" groups="pdk" />
   <project path="external/mesa3d" name="platform/external/mesa3d" groups="pdk-cw-fs,pdk-fs" />
-  <project path="external/messageformat" name="platform/external/messageformat" groups="pdk-cw-fs,pdk-fs" />
   <project path="external/Microsoft-GSL" name="platform/external/Microsoft-GSL" groups="pdk" />
   <project path="external/minijail" name="platform/external/minijail" groups="pdk" />
   <project path="external/mksh" name="platform/external/mksh" groups="pdk" />