package/pkg-generic: handle host-lzip as an extract dependency

This moves the host-lzip dependency handling from
DEPENDENCY_HOST_PREREQ to an extract dependency.

To achieve that, check-host-lzip.mk fills in the
BR2_LZIP_HOST_DEPENDENCY with host-lzip if building a host-lzip is
needed. The name BR2_LZIP_HOST_DEPENDENCY has been chosen because it
matches the name BR2_CMAKE_HOST_DEPENDENCY already used in
check-host-cmake.mk.

The BR2_LZIP_HOST_DEPENDENCY is added to all packages, except:

 - host-lzip, because we would otherwise depend on ourself.

 - host-tar, because lzip itself is delivered as a tarball, so we need
   to have host-lzip depend on host-tar, and not host-tar depend on
   host-lzip

 - host-skeleton, because we need to have host-lzip depend on
   host-skeleton, and not the opposite.

We also mutually exclude host-lzip and host-xz from dependending on
each other, to avoid a circular dependency.

In addition, we modify lzip.mk to explicitly build host-lzip without
ccache. We generally took the approach of building host-ccache *after*
all the extractors have been built.

[Peter: fix s/host-tar/host-lzip/ typo, fix s/xz/lzip/ typo]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
diff --git a/package/lzip/lzip.mk b/package/lzip/lzip.mk
index 4088662..7274224 100644
--- a/package/lzip/lzip.mk
+++ b/package/lzip/lzip.mk
@@ -16,7 +16,7 @@
 
 define HOST_LZIP_CONFIGURE_CMDS
 	(cd $(@D); $(HOST_MAKE_ENV) ./configure --prefix=$(HOST_DIR) \
-		$(HOST_CONFIGURE_OPTS) )
+		$(HOST_CONFIGURE_OPTS) CC="$(HOSTCC_NOCCACHE)" CXX="$(HOSTCXX_NOCCACHE)")
 endef
 
 define LZIP_BUILD_CMDS
diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index b03d726..f03f1d9 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -559,10 +559,14 @@
 $(2)_EXTRACT_DEPENDENCIES += $(BR2_TAR_HOST_DEPENDENCY)
 endif
 
-ifeq ($(filter host-tar host-skeleton host-xz,$(1)),)
+ifeq ($(filter host-tar host-skeleton host-xz host-lzip,$(1)),)
 $(2)_EXTRACT_DEPENDENCIES += $(BR2_XZCAT_HOST_DEPENDENCY)
 endif
 
+ifeq ($(filter host-tar host-skeleton host-xz host-lzip,$(1)),)
+$(2)_EXTRACT_DEPENDENCIES += $(BR2_LZIP_HOST_DEPENDENCY)
+endif
+
 # Eliminate duplicates in dependencies
 $(2)_FINAL_DEPENDENCIES = $$(sort $$($(2)_DEPENDENCIES))
 $(2)_FINAL_EXTRACT_DEPENDENCIES = $$(sort $$($(2)_EXTRACT_DEPENDENCIES))
diff --git a/support/dependencies/check-host-lzip.mk b/support/dependencies/check-host-lzip.mk
index 00cdd0a..cdd7840 100644
--- a/support/dependencies/check-host-lzip.mk
+++ b/support/dependencies/check-host-lzip.mk
@@ -1,5 +1,5 @@
 ifeq (,$(call suitable-host-package,lzip,$(LZCAT)))
-DEPENDENCIES_HOST_PREREQ += host-lzip
+BR2_LZIP_HOST_DEPENDENCY = host-lzip
 EXTRACTOR_DEPENDENCY_PRECHECKED_EXTENSIONS += .lz
 LZCAT = $(HOST_DIR)/bin/lzip -d -c
 endif