Use the bootstrap libphobos2.a when linking the initially built dmd.

Index: dmd-bootstrap/openbsd/bin32/dmd.conf
--- dmd-bootstrap/openbsd/bin32/dmd.conf.orig
+++ dmd-bootstrap/openbsd/bin32/dmd.conf
@@ -1,5 +1,5 @@
 [Environment32]
-DFLAGS=-I${TRUEPREFIX}/include/dmd/phobos -I${TRUEPREFIX}/include/dmd/druntime/import -L-L/usr/lib -L-L${TRUEPREFIX}/lib -L--export-dynamic -fPIC
+DFLAGS=-I%@P%/../../../dmd/druntime/src -I%@P%/../../../phobos -L-L%@P%/../../../phobos/generated/openbsd/release/32 -L--export-dynamic -fPIC -L-L%@P%/../../../dmd-bootstrap/openbsd/lib32
 
 [Environment64]
 DFLAGS=-I${TRUEPREFIX}/include/dmd/phobos -I${TRUEPREFIX}/include/dmd/druntime/import -L-L/usr/lib -L-L${TRUEPREFIX}/lib -L--export-dynamic -fPIC
