pkg-config-native,librsvg-native: fix EXTRA_NATIVE_PKGCONFIG_PATH

When building librsvg-native the variable PKG_CONFIG_PATH
was incorrect in the bitbake environment but handled correct due
to the pkg-config-native wrapper. Commit [1] and [2]
introduced some inconsistens of EXTRA_NATIVE_PKGCONFIG_PATH
where it was prepended in pkg-config-native wrappers but
appended in native.bbclass.

  meta/classes-recipe/native.bbclass:
    PKG_CONFIG_PATH .= "${EXTRA_NATIVE_PKGCONFIG_PATH}"

This commit will try to resolve this to always append the
EXTRA_NATIVE_PKGCONFIG_PATH. It is tested by building
librsvg-native and also checking bitbake environment
before and after.

[1] https://git.openembedded.org/openembedded-core/commit?id=2bc050146d47b14d890a1b0db2b55f9057a08b65
[2] https://git.openembedded.org/openembedded-core/commit?id=ae4824f4f6234884a245bce314d6305ad8eb982d

(From OE-Core rev: a59fa4a4bf08bbbd79fbb1642b3e3b23181f87c9)

Signed-off-by: Peter Bergin <peter@berginkonsult.se>
Cc: Alexander Kanavin <alex@linutronix.de>
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="$EXTRA_NATIVE_PKGCONFIG_PATH@PATH_NATIVE@"
+PKG_CONFIG_PATH="@PATH_NATIVE@$EXTRA_NATIVE_PKGCONFIG_PATH"
 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="$EXTRA_NATIVE_PKGCONFIG_PATH@PATH_NATIVE@"
+export PKG_CONFIG_PATH="@PATH_NATIVE@$EXTRA_NATIVE_PKGCONFIG_PATH"
 export PKG_CONFIG_LIBDIR="@LIBDIR_NATIVE@"
 unset PKG_CONFIG_SYSROOT_DIR
 

meta/recipes-gnome/librsvg/librsvg_2.59.2.bb

@@ -34,7 +34,7 @@ UPSTREAM_CHECK_REGEX = "librsvg-(?P<pver>\d+\.\d+\.(?!9\d+)\d+)"
 # for cargo to be happy
 BASEDEPENDS:append = " cargo-native"
 
-export EXTRA_NATIVE_PKGCONFIG_PATH = "${B}/meson-uninstalled:"
+export EXTRA_NATIVE_PKGCONFIG_PATH = ":${B}/meson-uninstalled"
 export RUST_BACKTRACE = "full"
 export RUSTFLAGS