python-selinux: fix cross-compilation, add test.sh

Add --no-build-isolation to PYTHON_SETUP_ARGS. Without it, pip creates
an isolated build environment which fails during cross-compilation
because _sysconfigdata is missing for the target arch.

Add test.sh with basic import and API sanity checks.

Signed-off-by: Alexandru Ardelean <alex@shruggie.ro>
(cherry picked from commit e2e727e686)
[keep version 3.8.1 from openwrt-25.12]
Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

lang/python/python-selinux/Makefile

@@ -7,7 +7,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=python-selinux
 PKG_VERSION:=3.8.1
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 SRC_NAME:=libselinux
 PKG_SOURCE:=$(SRC_NAME)-$(PKG_VERSION).tar.gz
@@ -51,7 +51,7 @@ endef
 MAKE_VARS += \
 	$(PYTHON3_VARS) \
 	$(HOST_PYTHON3_PIP_VARS) \
-	PYTHON_SETUP_ARGS=--no-compile
+	PYTHON_SETUP_ARGS="--no-compile --no-build-isolation"
 
 MAKE_FLAGS += \
 	SHLIBDIR=/usr/lib

lang/python/python-selinux/test.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+
+[ "$1" = python3-selinux ] || exit 0
+
+python3 - <<'EOF'
+import selinux
+
+# Verify key functions are available from the C extension
+assert hasattr(selinux, 'is_selinux_enabled'), "is_selinux_enabled missing"
+assert hasattr(selinux, 'getfilecon'), "getfilecon missing"
+assert hasattr(selinux, 'matchpathcon'), "matchpathcon missing"
+assert hasattr(selinux, 'selinux_getenforcemode'), "selinux_getenforcemode missing"
+assert hasattr(selinux, 'security_check_context'), "security_check_context missing"
+assert hasattr(selinux, 'context_new'), "context_new missing"
+
+# Validate context parsing (works without a running SELinux system)
+ctx = selinux.context_new("system_u:object_r:bin_t:s0")
+assert ctx is not None, "context_new returned None"
+assert selinux.context_type_get(ctx) == "bin_t"
+assert selinux.context_role_get(ctx) == "object_r"
+assert selinux.context_user_get(ctx) == "system_u"
+assert selinux.context_range_get(ctx) == "s0"
+
+print("python3-selinux OK")
+EOF