depends: add MULTIPROCESS depends option

Builds required packages and passes --enable-multiprocess option to bitcoin build

depends/packages/native_capnp.mk

@@ -0,0 +1,18 @@
+package=native_capnp
+$(package)_version=0.7.0
+$(package)_download_path=https://capnproto.org/
+$(package)_download_file=capnproto-c++-$($(package)_version).tar.gz
+$(package)_file_name=capnproto-cxx-$($(package)_version).tar.gz
+$(package)_sha256_hash=c9a4c0bd88123064d483ab46ecee777f14d933359e23bff6fb4f4dbd28b4cd41
+
+define $(package)_config_cmds
+  $($(package)_autoconf)
+endef
+
+define $(package)_build_cmds
+  $(MAKE)
+endef
+
+define $(package)_stage_cmds
+  $(MAKE) DESTDIR=$($(package)_staging_dir) install
+endef