mk: Clean libbacktrace w/ gusto

After `make clean' I'm seeing the build break with

```
cp: cannot stat ‘x86_64-unknown-linux-gnu/rt/libbacktrace/.libs/libbacktrace.a’: No such file or directory
```

Deleteing the libbacktrace dir entirely on clean fixes.

diff --git a/mk/clean.mk b/mk/clean.mk
index 73813a4b7512b41a8a32e1d5f16c4b0f47f3ab1d..34fd4d06fe5e6bad35e42870759d82c171ce50f3 100644 (file)
--- a/mk/clean.mk
+++ b/mk/clean.mk
@@ -78,6 +78,7 @@ define CLEAN_HOST_STAGE_N
 clean$(1)_H_$(2):                                                          \
            $$(foreach crate,$$(CRATES),clean$(1)_H_$(2)-lib-$$(crate))     \
            $$(foreach tool,$$(TOOLS),clean$(1)_H_$(2)-tool-$$(tool))
+       $$(Q)rm -fr $(2)/rt/libbacktrace
 
 clean$(1)_H_$(2)-tool-%:
        $$(Q)rm -f $$(HBIN$(1)_H_$(2))/$$*$$(X_$(2))