[openwrt/openwrt] build: use ccache -C for cleaning the cache

[LEDE Commits]

aparcar pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/cd5f66652bd405872fc33ca6410dc8f9b51fee09

commit cd5f66652bd405872fc33ca6410dc8f9b51fee09
Author: Sven Wegener <sven.wegener at stealer.net>
AuthorDate: Fri Jan 1 11:46:04 2021 +0100

    build: use ccache -C for cleaning the cache
    
    This keeps the configuration, like the size of the cache, and the
    statistics intact. Move the removal of the cache directory to the
    distclean target, but only delete the .ccache directory inside of our
    build tree, as we should not mess with a user-configured external ccache
    directory this destructively.
    
    Signed-off-by: Sven Wegener <sven.wegener at stealer.net>
---
 Makefile            | 2 +-
 include/toplevel.mk | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index f1577ad4d1..0144b0c5ff 100644
--- a/Makefile
+++ b/Makefile
@@ -64,7 +64,7 @@ dirclean: clean
 
 cacheclean:
 ifneq ($(CONFIG_CCACHE),)
-	rm -rf $(CCACHE_DIR)
+	$(STAGING_DIR_HOST)/bin/ccache -C
 endif
 
 ifndef DUMP_TARGET_DB
diff --git a/include/toplevel.mk b/include/toplevel.mk
index d3500ef58f..23bae149d4 100644
--- a/include/toplevel.mk
+++ b/include/toplevel.mk
@@ -261,8 +261,8 @@ package/symlinks-clean:
 help:
 	cat README.md
 
-distclean: cacheclean
-	rm -rf bin build_dir .config* dl feeds key-build* logs package/feeds package/openwrt-packages staging_dir tmp
+distclean:
+	rm -rf bin build_dir .ccache .config* dl feeds key-build* logs package/feeds package/openwrt-packages staging_dir tmp
 	@$(_SINGLE)$(SUBMAKE) -C scripts/config clean
 
 ifeq ($(findstring v,$(DEBUG)),)