update osm2pgsql (revert use of "char")

diff --git a/osm2pgsql b/osm2pgsql
index 28ce89dd28c20d94a98e29f41b8e76cfc7b6b823..c27acf17055ebe22c6363c293385865c624207f8 160000 (submodule)
--- a/osm2pgsql
+++ b/osm2pgsql
@@ -1 +1 @@
-Subproject commit 28ce89dd28c20d94a98e29f41b8e76cfc7b6b823
+Subproject commit c27acf17055ebe22c6363c293385865c624207f8