pigz: install pigz, unpigz, pigzcat in native and nativesdk builds again

* since this commit:
  commit ad1db93d134db1ec4f6d6598c9741dc13e82e1f3
  Author: Anuj Mittal <anuj.mittal@intel.com>
  Date:   Tue May 28 06:32:10 2019 +0800
  Subject: Revert "pigz: pigz is not gzip"

  pigz-native and nativesdk-pigz no longer installs pigz, unpigz, pigzcat,
  so scripts explicitly depending on pigz-native and calling pigz started to fail.

* reverse the logic
  - all the builds install pigz, unpigz, pigzcat
  - only the native one installs it as gzip as well

* it could be optimized a bit more to create gzip as just a symlink
  in native case as well, but they are in different directories
  (pigz in base_bindir and gzip in bindir) and it's only 130kB..

(From OE-Core rev: 112deafd1c144d770b6ec0953911f2adc1cb30dd)

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-extended/pigz/pigz_2.4.bb

@@ -23,7 +23,7 @@ EXTRA_OEMAKE = "-e MAKEFLAGS="
 
 inherit update-alternatives
 
-do_install_class-target() {
+do_install() {
 	# Install files into /bin (FHS), which is typical place for gzip
 	install -d ${D}${base_bindir}
 	install ${B}/pigz ${D}${base_bindir}/pigz
@@ -31,7 +31,7 @@ do_install_class-target() {
 	ln -nsf pigz ${D}${base_bindir}/pigzcat
 }
 
-do_install() {
+do_install_append_class-native() {
 	install -d ${D}${bindir}
 	install ${B}/pigz ${D}${bindir}/gzip
 	ln -nsf gzip ${D}${bindir}/gunzip