libxml2/host: revert xml2-config prefix fix

Commit 218f0229a4 added a workaround for a
problem. The host compile overwrote xml2-config in
"$(STAGING_DIR)/host/bin". The workaround fixed the issue for regular
target packages. But it didn't leave a proper xml2-config script for
host packages.

Times have changed. Host packages are now installed in
"$(STAGING_DIR_HOSTPKG). So there is no longer any danger of the host
package overwriting the xml2-config script for target packages. So
revert the mentioned commit, leaving us with two proper xml2-config
scripts, one for target package builds and one for host package builds.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

libs/libxml2/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libxml2
 PKG_VERSION:=2.9.9
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=http://xmlsoft.org/sources/
@@ -186,11 +186,6 @@ define Package/libxml2-utils/install
 	$(CP) $(PKG_INSTALL_DIR)/usr/bin/xmlcatalog $(1)/usr/bin/
 endef
 
-define Host/Install
-	$(SED) 's,^\(prefix\|exec_prefix\)=.*,\1=$(STAGING_DIR)/usr,g' $(HOST_BUILD_DIR)/xml2-config
-	$(call Host/Install/Default)
-endef
-
 $(eval $(call HostBuild))
 $(eval $(call BuildPackage,libxml2))
 $(eval $(call BuildPackage,libxml2-dev))