Propagate tags through opentitan_rom_binary

Bazel observes tags only for leaf targets when run with
--build_tag_filters so we need to explicitly propagate tags when emitting
rules. This allows specifying "all" with a subset of the targets based
on filters.

Bypass-Presubmit-Reason: previously tested

Change-Id: I048f025194888c53664d8a92edcf88699ca2f59d

rules/matcha.bzl

diff --git a/rules/matcha.bzl b/rules/matcha.bzl
index bf4886a..49fac79 100644
--- a/rules/matcha.bzl
+++ b/rules/matcha.bzl
@@ -148,6 +148,7 @@
         per_device_deps = device_deps("secure_core"),
         platform = OPENTITAN_PLATFORM,
         testonly = False,
+        tags = [],
         **kwargs):
     """A helper macro for generating OpenTitan binary artifacts for ROM.
 
@@ -160,6 +161,7 @@
       per_device_deps: List of devices and device deps to build the target for.
       platform: The target platform for the artifacts.
       testonly: The target is built for test only.
+      tags: List of tags to apply to each target.
       **kwargs: Arguments to forward to `opentitan_binary`.
     Emits rules:
       For each device in per_device_deps entry:
@@ -190,6 +192,7 @@
             deps = deps + dev_deps,
             extract_sw_logs_db = device == "sim_dv",
             testonly = testonly,
+            tags = tags,
             **kwargs
         ))
 
@@ -206,6 +209,7 @@
             bin = bin_name,
             platform = platform,
             testonly = testonly,
+            tags = tags,
             word_size = 32,
         )
 
@@ -217,6 +221,7 @@
             srcs = [elf_name],
             platform = platform,
             testonly = testonly,
+            tags = tags,
         )
 
         # Create a filegroup with just the current device's targets.
@@ -224,6 +229,7 @@
             name = devname,
             srcs = dev_targets,
             testonly = testonly,
+            tags = tags,
         )
         all_targets.extend(dev_targets)
 
@@ -232,6 +238,7 @@
         name = name,
         srcs = all_targets,
         testonly = testonly,
+        tags = tags,
     )
 
 def flash_binary(