pkgconfig: improved to create a symlink pkg-config -> ${arch_target}-pkg-config

Some Makefiles might not be smart enough and to have pkg-config in place
we simply create a symlink to ${arch_target}-pkg-config.

base/pkgconfig/pkgconfig.conf

@@ -29,4 +29,6 @@ if ! atstage toolchain; then
 	hook_add postmake 5 'cp -vf $confdir/etc_profile.d_pkgconfig.txt $root/etc/profile.d/pkgconfig'
 else
 	var_append extraconfopt ' ' '--program-prefix=${arch_target}-'
+	# create a symlink pkg-config -> ${arch_target}-pkg-config
+	hook_add postmake 5 'ln -vsf ${arch_target}-pkg-config $root$bindir/pkg-config'
 fi