For USE=debug to work, portage needs to run cargo_src_compile(), but if `emake`
is used in src_install(), it will trigger a rebuild without debug.  If
cargo_src_install() is used instead, manpages and symlinks won't be installed
and the binary would have to be moved since there's no way to make cargo install
to /usr/sbin. So remove $(PDATA_TOOLS) dependency in Makefile instead.  Might as
well patch out $(STRIP) too.

--- a/Makefile
+++ b/Makefile
@@ -56,10 +56,9 @@
 
 MANPAGES:=$(patsubst %,man8/%.8,$(TOOLS))
 
-install: $(PDATA_TOOLS) $(MANPAGES)
+install: $(MANPAGES)
 	$(INSTALL_DIR) $(BINDIR)
 	$(INSTALL_PROGRAM) $(PDATA_TOOLS) $(BINDIR)
-	$(STRIP) $(BINDIR)/pdata_tools
 	ln -s -f pdata_tools $(BINDIR)/cache_check
 	ln -s -f pdata_tools $(BINDIR)/cache_dump
 	ln -s -f pdata_tools $(BINDIR)/cache_metadata_size