gstreamer1.0-python: Set internal python library path correcty

The library hardcodes paths to the python library internally and currently
these are build paths. Fix this to use the correct target path and
fix reproducibility in the process.

(From OE-Core rev: 4c190e8c9a2b53de3def1065fb6e479b72d040dc)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/selftest/cases/reproducible.py

@@ -35,7 +35,6 @@ exclude_packages = [
 	'go-runtime',
 	'go_',
 	'go-',
-	'gstreamer1.0-python',
 	'lttng-tools-dbg',
 	'lttng-tools-ptest',
 	'ltp',

meta/recipes-multimedia/gstreamer/gstreamer1.0-python_1.18.3.bb

@@ -15,6 +15,8 @@ PNREAL = "gst-python"
 
 S = "${WORKDIR}/${PNREAL}-${PV}"
 
+EXTRA_OEMESON += "-Dlibpython-dir=${libdir}"
+
 # gobject-introspection is mandatory and cannot be configured
 REQUIRED_DISTRO_FEATURES = "gobject-introspection-data"
 UNKNOWN_CONFIGURE_WHITELIST_append = " introspection"