Add m target to grab the latest bitstream

Change-Id: Ie16513148ea8041fa040be4bd0ef436f5dcf4a24

platforms/nexus/matcha_hw.mk

diff --git a/platforms/nexus/matcha_hw.mk b/platforms/nexus/matcha_hw.mk
index 2fd416a..2c26cda 100644
--- a/platforms/nexus/matcha_hw.mk
+++ b/platforms/nexus/matcha_hw.mk
@@ -169,9 +169,15 @@
 	find "$(MATCHA_SRC_DIR)/bazel-out/" -type f -wholename "*fastbuild-*/sw/device/examples/spi_passthrough/spi_passthrough_fpga_nexus.bin" |\
 			xargs -I '{}' cp -f '{}' "$(OUT)"
 
+latest_bitstream: | $(OUT)
+	gsutil cp gs://louhi-cache/artifacts/nexus-bitstream_latest.tar.gz $(OUT)
+	cd $(OUT) && tar xf nexus-bitstream_latest.tar.gz
+	cd $(OUT) && tar xf results/fpga_nexus_smoketest.tar.gz
+
 
 .PHONY:: matcha_hw_verilator_sim matcha_hw_clean matcha_hw_verilator_tests
 .PHONY:: matcha_sw_all opentitantool_pkg
 .PHONY:: matcha_hw_fpga_nexus matcha_kelvin_fpga_tarballs
 .PHONY:: multihart_boot_rom
 .PHONY:: spi_passthrough
+.PHONY:: latest_bitstream
\ No newline at end of file