php: fixup paths in php-config for cross compilation

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/php/php.mk

@@ -171,6 +171,15 @@ ifeq ($(BR2_PACKAGE_PHP_EXT_PDO_MYSQL),y)
 endif
 endif
 
+# Fixup prefix= and exec_prefix= in php-config
+define PHP_FIXUP_PHP_CONFIG
+	$(SED) 's%^prefix="/usr"%prefix="$(STAGING_DIR)/usr"%' \
+		-e 's%^exec_prefix="/usr"%exec_prefix="$(STAGING_DIR)/usr"%' \
+		$(STAGING_DIR)/usr/bin/php-config
+endef
+
+PHP_POST_INSTALL_STAGING_HOOKS += PHP_FIXUP_PHP_CONFIG
+
 define PHP_INSTALL_FIXUP
 	rm -rf $(TARGET_DIR)/usr/lib/php
 	rm -f $(TARGET_DIR)/usr/bin/phpize