seastar: pickup alien fixes

Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/seastar b/src/seastar
index 52f0f389947b3cfd584da64a2867ce585ec046b8..2b392dec33e91c1fc5fb9eea04fbc08b078a874a 160000 (submodule)
--- a/src/seastar
+++ b/src/seastar
@@ -1 +1 @@
-Subproject commit 52f0f389947b3cfd584da64a2867ce585ec046b8
+Subproject commit 2b392dec33e91c1fc5fb9eea04fbc08b078a874a