pkgconfig: add pkgconfig package for target

The host versions shouldn't be visible in Kconfig, so remove the
reference to BR2_PACKAGE_PKGCONFIG everywhere and prefix the host targets
with host-.

At the same time add pkgconfig for the target (E.G. for development) and
let BR2_PACKAGE_PKGCONFIG control that package.

Notice: all defconfigs in the tree have been updated, but make sure to
disable the pkgconfig package (unless you want it) if you use an external
config, otherwise you'll end up with pkgconfig and glib2 in the target.

package/java/classpath/Config.in

@@ -1,6 +1,5 @@
 config BR2_PACKAGE_CLASSPATH
 	bool "classpath"
-	select BR2_PACKAGE_PKGCONFIG
 
 	help
 	  GNU Classpath, Essential Libraries for Java, is a GNU

package/java/classpath/classpath.mk

@@ -53,7 +53,7 @@ CLASSPATH_CONF_OPT = \
 		--disable-debug \
 		--disable-gconf-peer --disable-examples --disable-plugin
 
-CLASSPATH_DEPENDENCIES = uclibc pkgconfig libpng jpeg tiff
+CLASSPATH_DEPENDENCIES = uclibc host-pkgconfig libpng jpeg tiff
 
 ifeq ($(BR2_PACKAGE_ALSA_LIB),y)
 	CLASSPATH_DEPENDENCIES+= alsa-lib

package/java/jamvm/Config.in

@@ -1,7 +1,6 @@
 config BR2_PACKAGE_JAMVM
 	bool "jamvm"
         depends on BR2_PACKAGE_CLASSPATH
-	select BR2_PACKAGE_PKGCONFIG
 	help
 	  JamVM is a new Java Virtual Machine which conforms to
 	  the JVM specification version 2 (blue book).

package/java/jamvm/jamvm.mk

@@ -49,7 +49,7 @@ JAMVM_CONF_OPT = \
 		--disable-debug --with-classpath-install-dir=/usr
 
 
-JAMVM_DEPENDENCIES = uclibc pkgconfig classpath
+JAMVM_DEPENDENCIES = uclibc host-pkgconfig classpath
 
 #Include X libraries when we have an X server
 ifneq ($(BR2_PACKAGE_XSERVER_none),y)