[docs] Fix category for Starnix RFC

The original category of "PosixCompat" is not listed in _areas.yaml,
which causes RFC-0082 to not show up in the list of accepted RFCs on
fuchsia.dev. Change the category to the otherwise-unused "Foreign ABI
Compatibility".

Change-Id: Iee18da1e742888586009dee8c7ab4df2e78b1aa2
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/693242
Fuchsia-Auto-Submit: Alex Konradi <akonradi@google.com>
Reviewed-by: Kevin Lindkvist <lindkvist@google.com>
Commit-Queue: Alex Konradi <akonradi@google.com>
diff --git a/docs/contribute/governance/rfcs/_rfcs.yaml b/docs/contribute/governance/rfcs/_rfcs.yaml
index 37ab9d1..3e51ea1 100644
--- a/docs/contribute/governance/rfcs/_rfcs.yaml
+++ b/docs/contribute/governance/rfcs/_rfcs.yaml
@@ -1060,7 +1060,7 @@
   short_description: 'This document proposes a mechanism for running unmodified Linux programs on Fuchsia.'
   authors: ['abarth@google.com']
   file: '0082_starnix.md'
-  area: ['PosixCompat']
+  area: ['Foreign ABI Compatibility']
   issue: ['70225']
   gerrit_change_id: ['485181']
   status: 'Accepted'