Remove ccache from deps

Including ccache via the deps system makes little sense: this is a host
system tool, like the compiler, that should be installed in the build
environment.

contrib/depends/config.site.in

@@ -45,7 +45,6 @@ LDFLAGS="-L$depends_prefix/lib $LDFLAGS"
 CC="@CC@"
 CXX="@CXX@"
 OBJC="${CC}"
-CCACHE=$depends_prefix/native/bin/ccache
 PYTHONPATH=$depends_prefix/native/lib/python/dist-packages:$PYTHONPATH
 
 if test -n "@AR@"; then

contrib/depends/packages/native_ccache.mk

@@ -1,25 +0,0 @@
-package=native_ccache
-$(package)_version=3.3.4
-$(package)_download_path=https://samba.org/ftp/ccache
-$(package)_file_name=ccache-$($(package)_version).tar.bz2
-$(package)_sha256_hash=fa9d7f38367431bc86b19ad107d709ca7ecf1574fdacca01698bdf0a47cd8567
-
-define $(package)_set_vars
-$(package)_config_opts=
-endef
-
-define $(package)_config_cmds
-  $($(package)_autoconf)
-endef
-
-define $(package)_build_cmds
-  $(MAKE)
-endef
-
-define $(package)_stage_cmds
-  $(MAKE) DESTDIR=$($(package)_staging_dir) install
-endef
-
-define $(package)_postprocess_cmds
-  rm -rf lib include
-endef

contrib/depends/packages/packages.mk

@@ -1,5 +1,5 @@
 packages:=boost openssl zeromq expat ldns libiconv hidapi protobuf libusb
-native_packages := native_ccache native_protobuf
+native_packages := native_protobuf
 
 darwin_native_packages = native_biplist native_ds_store native_mac_alias
 darwin_packages = sodium-darwin ncurses readline