treewide: replace static mentions of repo name with dynamic ones

This does change the CONFIG_QEMU_FIRMWAREPATH to "/nonexistant", but
since we are using OVMF everywhere anyway this should behave the same.

Closes monogon-dev/monogon#343

Change-Id: I865e5ba5e62579c3ff1f31a25e46cbcb78dba688
Reviewed-on: https://review.monogon.dev/c/monogon/+/3450
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
diff --git a/third_party/musl/BUILD.bazel b/third_party/musl/BUILD.bazel
index 91d7398..1ce390c 100644
--- a/third_party/musl/BUILD.bazel
+++ b/third_party/musl/BUILD.bazel
@@ -27,10 +27,10 @@
     cmd = """
     OUT=$$PWD/$(RULEDIR)
     (
-        cd external/_main~_repo_rules~musl
+        cd {path}
         ./configure --prefix=$$OUT --syslibdir=$$OUT --libdir=$$OUT
         make -j $$(nproc) install-libs
     ) > /dev/null
-    """,
+    """.format(path = package_relative_label("@musl//:all").workspace_root),
     visibility = ["//visibility:public"],
 )