chore(3p/nix): Remove old build system and other miscellanies

There are still remnants of the old build system (for example, the
build derivations are not yet updated at all), but we'll get there.

third_party/nix/src/libstore/local.mk

@@ -1,60 +0,0 @@
-libraries += libstore
-
-libstore_NAME = libnixstore
-
-libstore_DIR := $(d)
-
-libstore_SOURCES := $(wildcard $(d)/*.cc $(d)/builtins/*.cc)
-
-libstore_LIBS = libutil
-
-libstore_LDFLAGS = $(SQLITE3_LIBS) -lbz2 $(LIBCURL_LIBS) $(SODIUM_LIBS) -pthread
-ifneq ($(OS), FreeBSD)
- libstore_LDFLAGS += -ldl
-endif
-
-libstore_FILES = sandbox-defaults.sb sandbox-minimal.sb sandbox-network.sb
-
-$(foreach file,$(libstore_FILES),$(eval $(call install-data-in,$(d)/$(file),$(datadir)/nix/sandbox)))
-
-ifeq ($(ENABLE_S3), 1)
-	libstore_LDFLAGS += -laws-cpp-sdk-transfer -laws-cpp-sdk-s3 -laws-cpp-sdk-core
-endif
-
-ifeq ($(OS), SunOS)
-	libstore_LDFLAGS += -lsocket
-endif
-
-ifeq ($(HAVE_SECCOMP), 1)
-	libstore_LDFLAGS += -lseccomp
-endif
-
-libstore_CXXFLAGS = \
- -DNIX_PREFIX=\"$(prefix)\" \
- -DNIX_STORE_DIR=\"$(storedir)\" \
- -DNIX_DATA_DIR=\"$(datadir)\" \
- -DNIX_STATE_DIR=\"$(localstatedir)/nix\" \
- -DNIX_LOG_DIR=\"$(localstatedir)/log/nix\" \
- -DNIX_CONF_DIR=\"$(sysconfdir)/nix\" \
- -DNIX_LIBEXEC_DIR=\"$(libexecdir)\" \
- -DNIX_BIN_DIR=\"$(bindir)\" \
- -DNIX_MAN_DIR=\"$(mandir)\" \
- -DLSOF=\"$(lsof)\"
-
-ifneq ($(sandbox_shell),)
-libstore_CXXFLAGS += -DSANDBOX_SHELL="\"$(sandbox_shell)\""
-endif
-
-$(d)/local-store.cc: $(d)/schema.sql.gen.hh
-
-$(d)/build.cc:
-
-%.gen.hh: %
-	@echo 'R"foo(' >> $@.tmp
-	$(trace-gen) cat $< >> $@.tmp
-	@echo ')foo"' >> $@.tmp
-	@mv $@.tmp $@
-
-clean-files += $(d)/schema.sql.gen.hh
-
-$(eval $(call install-file-in, $(d)/nix-store.pc, $(prefix)/lib/pkgconfig, 0644))