pkg-config-native: pick additional search paths from $EXTRA_NATIVE_PKGCONFIG_PATH

This was prompted by working on librsvg update: the new meson-driven
version wants to query values from .pc files residing in its own
build directory, and modifies PKG_CONFIG_PATH accordingly.

When using the pkg-config-native wrapper such modifications
have no effect, and we have to pass them in manually
from the recipe via EXTRA_NATIVE_PKGCONFIG_PATH variable.

This variable is already defined (with an empty value) and
appended to PKG_CONFIG_PATH export in the native class, so this
simply extends its use to the wrapper.

(Appending to PKG_CONFIG_PATH in the wrapper, instead of resetting it,
is not an option as that can lead to contamination with the cross values).

(From OE-Core rev: 2bc050146d47b14d890a1b0db2b55f9057a08b65)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/pkgconf/pkgconf/pkg-config-native.in

@@ -1,6 +1,6 @@
 #! /bin/sh
 
-PKG_CONFIG_PATH="@PATH_NATIVE@"
+PKG_CONFIG_PATH="$EXTRA_NATIVE_PKGCONFIG_PATH@PATH_NATIVE@"
 unset PKG_CONFIG_SYSROOT_DIR
 
 pkg-config "$@"

meta/recipes-devtools/pkgconfig/pkgconfig/pkg-config-native.in

@@ -1,6 +1,6 @@
 #! /bin/sh
 
-export PKG_CONFIG_PATH="@PATH_NATIVE@"
+export PKG_CONFIG_PATH="$EXTRA_NATIVE_PKGCONFIG_PATH@PATH_NATIVE@"
 export PKG_CONFIG_LIBDIR="@LIBDIR_NATIVE@"
 unset PKG_CONFIG_SYSROOT_DIR